Thanks guys,
Emailed back and forth with Smith & Wesson and was told that a 10 rd. mag(fits the med. & full M&P 45) is all that is now available but would leave 1 inch sticking out of the grip of the compact. Luckily I found web site that sold a grip adapters/sleeve made for the M&P45C. A solution but one that just ups the total price of a mag to over $50 each. Oh well, gotta have em