Silenus (Geoff) in the Bull and Castle may be able to help as he sometimes saves the swing-top bottles for himself or other ICBers.
As long as it has had beer in it they're ok pressure wise. You could also consider getting a tabletop crown capper so you could use any beer bottle. Myself and a mate got a few from Brouwland a couple of years ago, but we reckoned it wasn't worth it as we could get the same bottles (500ml mind) by drinking lots of Flensburger <!-- s:D --><img src="{SMILIES_PATH}/icon_biggrin.gif" alt="

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And you're dead right about how easy it is to assemble a collection in Germany. I currently have 9 crates, each holding 20 bottles, for homebrew use. A 50:50 mix of swing-top and normal I reckon. When you can buy beer cheaply by the crate it's easy to collect a few <!-- s:D --><img src="{SMILIES_PATH}/icon_biggrin.gif" alt="

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