The carbine replica sounds like more trouble than it would be worth to import privately. The frame on which it is built must have been "removed from the purview of the NFA", as detailed at
http://www.lugerforum.com/BATF2.html . While the final item on this list suggests the possibility of securing BATF approval for a short-barreled rifle built from scratch, I doubt that this process can be effectively coordinated by the members of this forum. Nevertheless, I would be all too happy to be proven wrong.
Importing the Swiss surplus M1906/29 would be much easier. I will finance and coordinate a wholesale shipment, given enough retail interest from the assembled audience, and agreement on the terms and conditions of the transaction.