I agree with Turboned, the wheel needs to have a nice flat look IMHO if you are picking a style. My Uno Turbo has 15s on it that SteveNZ originally chose - I agree with his choice too
Those wheels are pretty anonymous - conservative by modern standards. They're probably heavy as well. I think, given the choice between old, radical styles or modern conservative styles, the former's probably more in-period for the Uno. E.g. 'BBS-style' wheels with the lattice spokes.
I think that wheels off a Croma Turbo would be a good choice for the Uno Mk1 - properly cleaned and polished, of course. They look exactly like Uno Turbo Mk1 alloys, but are 14". There probably aren't many Croma Turbos left in England? You can turn it into an interesting challenge finding original wheels and restoring them. I've improved Uno Turbo wheels by using paint stripper to remove all the flaking lacquer, then jacking the car up and, having the engine idling in 4th gear, holding a sanding block against the wheel.
Other good candidates would be certain Alfa Romeo models, e.g. Alfasud Sprint Cloverleaf, some of which came with 14s. Presumably the bodywork has disappeared by now, so there should be wheels left over?
It's interesting when you think about what wheels go with what period. I recall trying to buy 4x98PCD alloys brand new for my 128 Coupe in 1998. The only wheels you could get were Minilite-style. I think they look good on '60s cars (and Minis, strangely enough). The Lancia Beta wheels I ended up using actually looked better on an Uno (being '80s).
Lancia Thema Mk2 models (e.g. 16v) had some nice five spoke alloys which I think were 15s.
-Alex