Hi Jim, it's all very easy, if you can find a like minded person in the States you can bring in AOs into UK with no problem, but you must state on Customs form that it is an Antique Curio sec 58.2, with no 38 centre fires or alike getting through as they do, Customs open most packets from the US to UK, most days of the week Customs in UK pick up modern firearms like ppks etc, they don't make it to the new owner & are destroyed, so be mindfull, as for sending AOs to the States it's a nightmare, ATF do not want them.
But I do have some very good contacts in PA & TX this works very well as I have been dealing with some of them for over 15 years. I should think you being on the otherside of the pond have a great chance of finding SAA & Smoots at fairly good prices at these gun shows you do over there. Take a look at the AuctionArms.com they have loads of great AO deals & it's all in the USA lots of Private & Trade sales.
ATB, Glynn.