I would say your probably stuck hard wiring these to your power supply. You can Google waterproof led power supplies. I looked into this a while ago and found several for sale online through Google and Amazon.
I ended up not needing the bigger power supply for my project (stringing 3 sets together in series), I went a different route.
I’m not sure you would need a 50 watt power supply to do what you want. If I remember correctly each set at 100% draws around 6 watts.
We discussed this in some detail in this thread around post #111 to say 130ish.