Outdoor led strips

The power supplies for white LED tapes are reasonably generic. Any power supply that outputs the same voltage, same current type (AC vs DC) and at least the same wattage or current will work. If you can find a suitable supply you can probably use it with the Costco tape.

However, I don't know if there are wall-wart style power supplies available that will be powerful enough to drive 25 feet of LED tape and small enough to fit under the in-use cover of an outdoor receptacle.

Unless someone else can suggest an outdoor cord connected power supply, your best option is probably to put a power supply in a weather-tight enclosure and connect it to power with an outdoor extension cord. Alternatively, you could mount the power supply indoors (or under the deck) and run heavy-gauge wiring from the supply to the LED tape.

Lee Valley has indoor cord-connected 12V power supplies that may be suitable for use inside an enclosure. Search for part 00U4189. Alternatively, try DigiKey, Mouser, and the other electronic parts suppliers.

Try solar light strip from Amazon. I had bought couple strings from there.