Found a loose bolt on the forward stay of my rear rack that was the source of some squeaks. Tightened it up no problems, while I was there with the 5mm allen key I thought I'd check a few others. Nipped up the mounting bolt of the rear v-brake and it rolled the pad onto the rim. And stayed there.
Busted the little pin off the southpaw claw that goes in to the little hole next to the male bit

Assuming I'm up for a new brake now... Current one is a Tektro RX3, but if there's clearance I might get a Tektro 926AL which is 5mm shorter but probably better suited to drop levers if I ever get round to that conversion...