I have no experience with medical tattoos, but plenty with tattooing in general. If you live in a major city, or near to one, you shouldn't have a problem locating a talented tattoo artist. Just google tattoo shops and read the reviews, check out the artist's portfolios. Find a couple that you like and visit their shops to check them out, they'll probably have a larger portfolio for you to view in shop as well. Make sure to communicate very clearly what you want to the artist. I think as long as you find someone who is both a talented artist and skilled tattoo artist (yes, sometimes they are not both), they should easily be able to create what you want.