It's not needed. You can list on the US site from your ebay UK account. If you have turbolister, there is a drop down in the upper right hand corner when you set up an item or template that let's you choose the ebay site to list on.
For example I have a US account and a US store but I also list some store items directly on the ebay UK site, the listings are separate from the US store listings, I had to rework my template to include the £ sign and refigure things from the UK perspective, but no problem. All turbolister listings have a flag next to them indicating which country the listing for. My UK store listings are 9p each but they are worth it.
Also for auction/fixed price items you can now get International visibility for 10cents extra. That means when I list an auction item on the US site I can pay an extra 10cents to also have that item listed directly in the UK auction listings. That option is in the listings upgrade section of you turbolister files. Update on that happened last week. It works the same for UK ebayers pay an extra 5p ?, to get your items directly on the US site.
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