Thanks very much for the suggestions everyone. If I was to go for a triplet lens (obviously for a reasonable price), how likely am I to see a huge reduction in quality? A lot of the cameras suggested here run a bit over my £200 budget, at least here in the UK. The few that fall under that seem to be in a rough state (lens separation, fungus, haze etc.) So it may be more sensible to buy one in a better condition.
I've heard that triplets stopped down to f8 or f11 perform pretty well. I'm not really looking for optical perfection, I still would like the pictures to look shot on film!
My favourites so far are the Yashica Mats and the Minolta Autocord, although normally looking on that online marketplace, they start in the lower 200s+. If a CLA is in order, how much could I expect to budget for that?