Albion, like you I'm on this side of the pond, ie the English side.
And like you I was shocked at the difference in price between ABs in the UK and the US.
I ended up buying an Omni 4000 from BearAir in the US, as I wasn't too impressed at the response I received from Dixieart. Bearair can be found at www.bearair.com, and I know of quite a few other people who have used them.
The Omni is a great AB, and cost me about £38!
The downside is that the shipping and customs added about £45!
That still works out at only £83 for a brand new double action AB from a known manufacturer, and shipping only took about 4 days.
Because the Omni is not available in the UK spares can appear a problem, however Shesto stock many of the common spares, as they are the same as for some of the Badger and earlier Vega brushes.(Correct me if I'm wrong on this Mike)
If you don't fancy the import route, try www.mainlytrains.co.uk, don't be put off by the title, as this site stocks a wealth of stuff all types of modelling, and they usually deliver within 48 hours. They stock a Badger 100 for £89, or a Badger 155 Anthem for £95. The 100 is gravity fed, while I think the 155 is a syphon feed.
Sorry for the length of the post, but I hope it helps.
If you need any more info, give me a shout.
Karl