Well surely you already have the single engine piston class rating on your licence? In which case you'd probably only need a check out at a club.
I'm sure many schools/clubs operate the PA28: Caernarfon have a nice new one which I've got quite a few hours on and Sherburn-in-Elmet have a about 6 of them. Pretty sure Ravenair at Liverpool/Barton operate the type, as do a couple of schools at Blackpool.
B