Thanks Con that could be a good resource.

PC I thought your 585 had a pacnor barrel?
By the way the bullets from tenring have turned up.

Errr Con, watch it here.
Firearm barrels most definitely require export license @ US end and import permit @ this end.

Do you really want to risk a "suspected terrorist" style raid? That's what you're likely to get, these post 9/11 days, if Customs open and inspect your parcel. And they'd have the names of major US firearm part suppliers in their computer. My last parcel from Brownells got inspected, tho' it only had tools and cleaning bits in it. FWIW, the word 'gun' was mentioned on the value declaration [pro forma invoice] though.

Just another point: Would the barrel be short chambered, or full chamber and 'long shoulder'? First situation still needs the reamer, second doesn't, but in either case your smith will need the headspace gauges.