I get what you're saying, but if you find a solid portrait artist, this won't be an issue so long as you provide a high quality photo of your pet and exactly what you want in the tattoo. A great portrait artist isn't going to screw it up.

Wish I could better answer your question, but all great artists I know don't do it this way. They're too busy and too talented. My advice is to spend the time finding the right artist, even if it isn't local.