[wagonman76]

I like the idea of plastic sleds. As winter ends they are probably on clearance for dirt cheap too. That might be an option if my coroplast discs ever come apart. Right now I have coroplast discs taped to my trim rings and then painted over. I could get a set of junkyard trim rings (so I don't screw up my originals) and bolt the appropriately cut plastic sleds to them with small screws and nuts.

As far as mass production, probably just not the market for them. Back when hubcaps were the norm, you still hardly saw any moon discs as it was. Now most cars seem to have alloy wheels so any market would be even smaller.