Strange you've not received a reply yet. I'll bite. I have. Got them from a company in B.C. called Canada Sled Parts. Great to deal with. As for the adaptors, they're fantastic. If you have enough tunnel room for two sets you can get linq foot kits from BRP to build your own rack or box set ups. Definitely a good upgrade IMHO as no other OEM comes close to BRP in terms of quality accessories.
Cheers!