There are
There of several people selling it on eBay UK, but none in the US apparently.
http://cgi.ebay.co.uk/DIY-UPHOLSTERY-SUPPLIES-PIRELLI-RUBBER-WEBBING-ERC...
To Confirm on M andersen
Hi The springs you need are called xperweb and FAGAS are THE supplier you need.
Ever so simple to fit as the spring comes on a roll and you cut the required length of. A small piece of thread simply fits into the ends you have cut and there you have it!
Simon
Danish homestore
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