Not sure where to get resin copies, have you looked in the parts thread to see if anyone is getting rid of theirs?
Sorry to hear about your run-in with nail polish remover. For future reference, nail polish remover is not a kitbasher's friend. If you do use it, only in minute amounts. (even then, I can't think of it being a good idea.)
Can you get a picture of the purple paint you're using it? I'm not sure on if it's too dark or not. Either way, when you're doing a dark on dark color, you might get the best effect by putting a lighter color(like a gray or white) on top of the source/base piece, letting it dry, and then topping it with the new color.
Hope this info'll be of some help.