Flip-face Toby tram roof paint query

I recently purchased a flip-face toby that had some marker etc on the tram roof. I used some goo gone to gently (and succesfully) remove the marker (I then cleaned the rood with water to get any goo gone out of the picture). But then I couldn't leave well enough alone, and decided to try to remove what I thought was some gunk, but ended up removing a spot of paint. So there is now a brown spot showing through on the roof. Not the end of the world, but I was wondering if anyone had suggestions for touching up the roof? I have a feeling matching the white/greyish color will be tough, so it may be that I should plan to just pick a shade and try to repaint the whole roof. And I also have no clue what type of paint would most closely match the texture of the original (acrylic?). Thanks for any and all opinions!