The folks at Bearclaw (kydex) most likely will make you one. www.bearclawholsters.com
I have several holsters from them and although the pup is not listed on their site the owner said he will make one. I love their product - have a few of their holsters for my 1911's & Kahr.
I just received my Hoffner IWB for the Rohrbaugh yesterday. Its a kydex J hook and first impressions are very positive. I will post back here on how its working once I have had the chance to wear it for a week or so.