I have yet to have a problem finding and buying POC shafts.In my view, Rose City makes some pretty decent POC shafts. You can get them there, or supplies stores like Three Rivers, Kustom King, or others.
Wapiti makes some very good POC shafts too that are nice shooting.
I use shafts from all those listed and have great luck with them. All have proven very tough for POC, and very effective at the target or on the hunt. I dont know what else a guy needs. One thing I do recommend, is either buying them in group weights along with spine, or have the ability to weight and group them yourself. In the case of the latter, you'd do best to buy bulk to insure enough matches to make your dozen(s).