John, I have carried the R9 for a while. Just now making it to this forum. If an order is placed, I will take 2 of the unplated or 2 of whichever style you are making. As an FYI, I also have a Seecamp and ordered mag extensions from Jeff, Owner, at Sigpower.com. He seems to also do the machining. I asked him if he would make some extensions for the R9 and he said that he would like to but does not have one to model. Jeff seemed very willing. You might want to check his site and call him at 1.423.293.0196. The reviews are excellent on his Seecamp mag extensions... BTW and if you decide to also make the curved extensions, I will also take some of them unplated if possible.
Raul