Contact Nicolai directly - keep in mind they're ridiculously expensive and usually frame only - you have to buy the shock separately, so the retails prices are even worse. Plus, the M-Pire isn't made anymore, which is a huge bummer, because it was the best hardcore DH frame they ever made.
Nicolai is a company in Germany, but they do have a US presence as Nicolai USA. All the manufacturing and engineering happens in Germany though - the US branch is just a distributor essentially.