I am not familiar with any company that sells that. But PDL coating of plates is very simple to do, especially if you dont need coverslips like in your case. You can get 10mg of PDL for 300 bucks, and for coating in plastic a 20ug/ml solution should be more than enough, probably 30 to 50 ul per well. You can just coat for 1 hour at room temperature and then wash with water once, although I usually coat plates overnight, but I work with coverslips. Sometimes I do 1-2 hours at 37C. Good luck