Another option I found is a (I think it's a beaver) trim weight. I've got a 2Kg one that is a rectangular bag of shot with a loop of webbing on one side to attach to a cam band, but more usefully it has two eyelets at either end. It's not as nice as a v-shaped weight to hang off the bottom bolt, but it fits, it was in the shop when I was messing about - and hey, it's black
