You'll need to have the services of a company that is set up to do import-export of firearms.
They'll handle the import procedures and will receive the guns into the US.
They will then ship the guns to your local FFL Dealer.
The guns have to be of a type that can be imported into the USA.
A good company to talk to about this is Cherry's, who offer import services:
They have some info on the site, but you'll have to actually talk to them.
Cherry's Fine Guns Home Page Commemorative Firearms