I have a spider lily weight with an unusual pontil BPK for the Big Pine Key Glassworks, it is going on ebay soon I think. I also have a Jennings Bonnell frit weight with his JB Pontil mark, various St Clair, Joe Bob & Maude, then I have weights with Gibson and Prestige and Gentile impressed pontils.
Liskeard Glass did an impressed LG Pontil but they also made weights for St Tudy paperweight centre and I have one with ST 1976 impressed but when this moved to Yelverton they made more and I have one with Y1981 in the base
Hope this helps - although you probably know most of it I guess
Dave