......however when looking for these power boxes, they seem to only be available in the UK. Whats the deal?
Seems to me I've seen weather proof boxes. Have you looked at your "big box building supply store" or electrical supply house? I've buried powerline to outlets outside...
it helps with the Christmas lights. I have also used appliance modules in a used (and cleaned) jar and some cord siliconed into the lid.
But now I have the (no-longer made) Black and Decker outside modules.