It looks like a Wairfair piece. I say that because I LOVE bombay design and have looked at hundreds of pieces. Chances are the paint job was done in a horrid sweatshop in China--took some poor worker maybe an hour. Google bombay hall chests. I found a few options that seem like your mirror frame. Pictures are difficult for such things. It would not be odd for a piece of that shape to be finished as you would prefer. Pinterest also has some options.

It's not an antique and I agree it's probably a Chinese piece and although sweet, if you don't like it, I would have no problem in painting it and yes, I think your mirror and the piece are not compatible and the mirror would look better with something different under it or the chest would look better with something different over it. So paint away!