I just got one of these for my M&P45 Compact...
http://www.psholsters.com/
Similar to a raven concealment. I love it so far. Best IWB Holster i've ever run, and i've run more than a few...
I ordered it with the ultimate IWB Package here. Look under belt attachment methods. There are lots of options. Only downside from your perspective, is you would have to change out the loops to switch from OWB to IWB though.