Hi Pietch,
Welcome to the forum.
I thought that Chas had the best answer! Dave was right too but possibly a bit harsh (he made it sound as though it would be unlikely to have much demand, where in fact Mk1 3-dr bodyshells have solid demand as far as I can tell).
Just have a look at Dunc's Uno Turbo Restoration Thread (under Let's Talk FIAT) for proof that a 'donor' shell is very useful (and not just for making a show car, more a case of economic rust repairs for any rusty Uno Turbo).
Then perhaps do some eBay searches in Completed Listings (Advanced Search) - you have to be registered as an eBay member to do this.
Pottleflump, Ha, those prices are so low by our standards in NZ...
'Tidy' but not very original (and certainly not mint) Mk1 5-door, I sold last year for equivalent of 450 pounds.
Rather tatty and not-original-at-all Mk1 3-door, a friend sold for equivalent of 260 pounds.
Mk1 Uno Turbos here in NZ seem to be hitting 1100 pounds-equivalent in private auctions, which is pleasing. I saw a Mk2 sell for the equivalent of 1400 pounds at auction. There's a nasty-looking Mk1 for sale here at the moment, de-registered (which means a $500 cost to get back on the road, if it can pass the tougher inspection) and even that has passed $500 (185 pounds) on parts value alone.
http://www.trademe.co.nz/Trade-Me-Motors/Car-parts-accessories/Fiat/auction-57153278.htm
What makes this price difference even more interesting is that our wages/salaries tend to be about half those in the UK...
-Alex