I nipped into Tesco's for some mushrooms this evening, and spotted some fruit on offer. It's just standard basic varieties as you'd imagine, but I got a Williams pear to replace the one I had. That's all three trees which died in the drought or soon after replaced now. there's no indication of rootstocks, but the label does say that my tree reaches about 4 metres, which suggests it's on the common Quince A stock.