easiest will be to replace the whole chair if you can find a decent one.. You would have to find one to get new cover anyway - You could get a whole set of seats instead say from a GT which would bolt straight in without modification or if you feeling fancy fit some from another car but the bases will need modding to make them fit.
Failing all that a cheapo universal cover but i do loathe them myself, i'd rather have a ripped chair lol.
These for example would do,
http://www.ebay.co.uk/itm/Fiat-punt...arts_Vehicles_CarParts_SM&hash=item1e7b6c5eab
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