Some of the retailers/manufacturers here can chime in also I'm sure, but PayPal has been increasingly difficult to accept payment for anything remotely interesting lately. I've seen companies have PayPal completely shut off processing on them just for having a single regular supplement with a single ingredient that is completely legal, but just that PayPal "doesn't like". They don't even give you any warning before shutting you down. So I'd really be shocked to see anyone selling RC and able to accept it to be honest.
I've also moved this thread to the Peptide/Research Companies section of the site since it does not fall under the "Supplement" section.