The only thing I could think of which seems plausible would be to approach a rug business and impress upon them the saleability of a mandlebrot design so much that they put one into regular production. The only company that comes to mind for me would be Trans-Ocean, but I can't find any contact info with a very cursory search. My google-fu sucks this morning.

You might do a search for them through - perhaps you'll actually find a rug which already exists that you'll like, they make quite nice stuff which wears nicely. I've no idea how availability in the UK is, however.