IRD makes 10spd cassettes with MTB range. Now that SRAM has launched XX for MTB's, that should work as well, but at a healthy cost. The new XX rear derailleur is supposed to be cable-pull-compatible with SRAM road shifters.

An even better option for touring, particularly in your case, is to go with a Shimano bar-end and matching long cage triple Shimano rear derailleur.