There are sometimes pieces in Carnelian Crafts in Crieff, Gary.
Have you been to Crieff at all recently? There's an antique shop attached to Caithness/Dartington glass, it sometimes has good interesting bits - and the lady who is running Carnelain Crafts and making some rather lovely fused glass pieces is the widow of the chap who ran PPs. I'm thinking you might be able to pick her brains about PPs - she does sometimes have PP glass too (and you at least see pws in both places. I rather like Peter MacDougal's contemporary work - even if it is pws.)