Rich, if you open the image in Photoshop and rotate it a few degrees, recrop it, etc... there's no way anyone could prove it was his image, and not a new scan of the same chip. The key is the rotation, which forces a resampling so that there are no identical pixels. I'd never recommend this in any other situation, but since he's selling counterfeits...

Also, I'm not claiming any legal expertise, but I would think you could publish a PORTION of the scan under "fair use", in the same way that copyrighted works are quoted and movie reviews show brief clips. That might be enough to show the tell-tale features of the fake engraving.