What are these LED power supply plugs called?
These look like DIN loudspeaker plugs. Odds are you could find some extension cords for those too!

I'm not sure how would you still source them, these new connectors aren't very new at all, and seem to be quite rare these days. One can still apparently find these listed on our favourite auction sites and the like as B&amp;O connectors, as the brand still seems to use those. There also were 3- and 4-pin versions, but those now seem to be much, much more obscure!

See here:



(Image taken from here)