Hello! I'm not in Michigan but I wanted to say good luck with your search. I would reccommend visiting this website:
Biewer Terrier Club of America. You should he able to get into contact with a reputable breeder who registers their dogs with the BTRA. I personally wouldn't work with anyone willing to trade antiques for a living creature, so just be careful that you aren't dealing with a broker, puppymiller aka greeder. If they are willing to give you a dog for a lamp, they probably cut corners on important things like vaccinations, genetic testing, etc...costing you more money in the end!
Also bumping this so that our several Biewer breeders here on YT can better advise you
