I got mine from a local club member, also was selling it on CL. Ended up being some pretty good rock, cured, cooked, clean and has tons of life and so far no pests, knock on wood. I had the same issue finding rock, LFSs had no good life rock just cheap crap mined rock or expensive man made dry rock, any wet roxk was fake or looked like white round boulders. Found some online from places like the Gulf and Philippines also the Walt Smith Florida cultured rock but was very expensive plus shipping costs.
I think what needs to happen is more cultured rock, man made or mined then made life or cultured either in the ocean of a year as WS does or in a captive system designed to make dry rock live jast like it would in our reef tanks over a time. Something I have considered doing but lack the resources to make live rock. Would be a least a year before any product could ready for sale and a lot would be needed.