Can I convert my v-brakes to cartridges?
There are plenty of cartridge pads for MTB v-brakes.
For example http://www.ebay.com/itm/Cartridge-V-Brake-Pads-with-Titanium-Finish-for-Shimano-XTR-XT-SRAM-9-0-Avid-/200719390579?hash=item2ebbced773:g:auQAAOSwJSJXGDxZ .