In addition to having the door powder coated, I also ordered two brand new coin mechs from Asahi Seiko in Las Vegas (they still make them!) so the entire thing now looks factory fresh. It was EXPENSIVE ($93 for the new mechs!). Here is what the old mechs looked like - these were unfixable to me with the rust and everything (not so much on the outside but around the coin return button):
It took about a week for the new mechs to arrive but it was worth the wait. Here's some unboxing pictures for the full effect:
They look great. Next up - final installed coin door pics!