Whereas my elegant, ladylike, fingers find the PO8 a perfect fit. At least the real one, I've never used the CO2 replicas.

You might want to look into the Umarex 5/686, Umarex 92FS, BSA Scorpion, and the Gamo Falcon. All are suitable for the larger hand. The last has a truly huge ill-shaped grip that might suit you.