I have a couple ideas:
a) Easiest solution is to put some text on the page, maybe a red box above the add to cart button that says something like "This product is not available in Michigan". You can use Liquid code to only show this message for the specific products.
b) If you implement solution A but find people are not seeing the message, you can force them to select their state before adding to cart. On the product page, put in a dropdown with all the states, and disable the add to cart button until the user selects a state. If they select MI or FL on the product, then show a message saying you can't ship there.
c) If you want to guarantee preventing the shipping you can make separate shipping profiles. Go to Settings > Shipping and Delivery and set specific shipping zones excluding those states for those products. Then the user will not be able to select a shipping rate for that product.
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