I got mine off ebay-UK, I think the total price was 200. 80 for the engine and 120 for shipping. It was used and I had to rebuild it, but luckily the manufacture was still around an willing to send me some replacement gaskets for free. The hard part about this rout is finding some one willing to ship from the UK, there are a ton of engines for sale there for cheep.
Did you check out Northern Brewer? they are selling cask equipment. they have a
pullman pump new for 450...