Looking for advice dealer refuse to return deposit

Dear RFDer,

I'm looking for advice what I should do when dealer refuse to return deposit. It would be great if anyone has similar experience and willing to share.

I signed a contract to purchase a new car. On the contract it says distance travelled is 150km. However, the dealer took a few pics for me and the mileage is 473km on the vehicle. I told the sales it's not acceptable as it's way more than the number on the contract. The sales told me it's because of dealer trade. I verbally agreed the trade but they never told me how it works. However, I checked the distance of the other dealership and it's only 100km from me.
Today I got a call from the manager. He's very rude and told me to take the car by the end of tomorrow, otherwise I'll either lose my deposit, or the price will change next month and he will sell other cars at MSRP to me.

Here are the things I have done:
Call OMVIC. The rep told me it's a grey area. If the dealer refuse to return my deposit, I have to go to small claim court. But it's possible that I have to take any cost of the dealer trade.
Call GM. The rep submitted a case for me
Call credit card company. They could refund but if the dealer provide any "evidence", I will still get charged.

I'm not sure what's the rule on the forum so I'm not going to release the name of the dealership. I appreciate if you have any suggestions.

Edit: The dealer is Eastside GM. Close to the Woodbine Costco in Markham.
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Update: got a call from the sales, she's willing to give me some freebies or renegotiate a new car. She told me the car has been registered under my name (I have no idea before the call), and there will be a loss if I decide to walk way from the contract. They will charge the cost on me. She also mentioned they have an internal "rule" that dealer trade is allowed to take up to 600km. So they are protected. However, they never told me that and it's not on the contract either. Is that something that I supposed to know? I was really pissed off yesterday by the manager, so seriously I don't want to do business with them again. If they offer me yesterday I would probably take it.
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Update 2: I filed a complaint to OMVIC last weekend and I'm quite surprised by their reply.

"In Ontario, a signed vehicle purchase or lease agreement is final upon signature. Whether the agreement will be cancelled is at the discretion of the seller. Should the seller agree to terminate the deal, they’re entitled to retain your deposit in order to recoup losses incurred as a result.
As your deposit was $1000, it’s highly likely the dealer’s damages meet or exceed this amount."

So it sounds like dealers are kings and they can break the contract but consumers can't refuse to take it. I asked for further explanation and got the following.

"When buying a vehicle in Ontario the dealership is required to include the vehicles odometer reading but they are allowed a variance of up to 1000 km’s. If the vehicle was delivered with a difference of more than 1000 km’s on the contact, then you would be allowed to cancel the agreement. The variance in this situation was 323 km’s, meaning this isn’t enough to trigger a cancellation in your complaint."

Wow, the dealer can travel with your new car up to 1000km and you have to accept it. They also don't have to release such "rule" and it's not on the contract either. Sounds like a great free road trip with a brand new car from Toronto to Montreal.
As pointed by RFDers, OMVIC is wrong.

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Update 3: Got an email by the manager.
"So these are your 3 options now:
1. Pick up the vehicle by Monday May 10th. Although Costco promotion has ended new GM employee pricing is a lower price. The residual value however has reduced resulting in a higher payment. As a gesture of good will we will take a further loss on the vehicle by $200 to match the April payment. Although not necessary we are trying to accommodate this situation. Client will not get the Costco gift card as that promotion is over. We have removed your plates and it will take us 1 business day to reissue them.
2. Wait 1-2 months if not longer for another vehicle to be shipped in brand new under 90km. Pricing will be subject to the programs at that time which may result in a higher payment but we will do our best to give you the best available deal.
3. We will refund you your $1000 deposit less all expenses incurred on your deal. We are not looking to profit from this and the deduction will go towards paying the costs incurred and ensuring the staff involved are compensated for their time. Please keep in mind that we also had to trade a Trailblazer with lower kms (different colour) to get the one you requested."