MI Native:
Tilapia is not on the outlawed species list in MI. You may use in your pond but the issue is getting a big enough supply of adult TP to your pond. You can order fingerlings online but you need about 20-30 pounds of adult as a recommended stocking. THen, the problem is that the adults don't do that much eating, but if they have a few successful broods, the thousands and thousands of young mouths eating will make a dent in the weeds. The growing season in MI ponds is short and the fish don't lay eggs till water hit a certain temp. Then of course the adults and the young all die off in Nov when water temps hit 50-55 depending on what strain of TP you have. So the next season you have to start over again.

I only know of one fish hauler with necessary permits to haul TP into SW MI so you could connect with that outfit and when they bring TP to other SW MI ponds you might be able to get in on some. Perhaps there are other haulers in the SE part of the state but doubt if you are in mid or northern part of MI or the UP that you have options outside of shipping in 1-2" TP.