All you would need is a new barrel (18.5 inch criterion), a springfield armory scout scope mount and a scout handguard. Wolverine supplies should be able to get the mount and handguard no problems. The barrel would be a little more difficult as it requires import/export paperwork. The reason I think you'd be better off with the new barrel rather than a chop job is that a USGI flash hider (and the coast guard one) requires some indexed slots to be cut in addition to the regular crowning/threading associated with a barrel parting job. A newly manufactured 18.5 inch barrel would have these slots already cut, and you can be guarenteed they are cut appropriately. I'd be looking for a US source for the barrel and get questar to handle the import/export paperwork for you.
Good luck....
Brobee