Shipping one Percolator, kit or prebuilt, to UK (or most anywhere in EU) costs about $60 USD. The Combo costs about $68. Customs situations vary widely and I’m afraid we do not keep very well up on this. Perhaps a UK customer can comment?
Our dealer in Paris, Woodbrass Deluxe, has Percolators, Cabs and Combos (ready to play, no kits) in stock at woodbrass.com. Please check them out! You may find their pricing (and quick availability) makes more sense than trying to buy direct.