Hand crossbows specify that you TWF with them as light weapons, so I would say that pistols and firearms of similar weight would fall under similar rules, considering the Pale Stranger wields its pistols as light weapons, penalty-wise.
The 1 handed reload was possible in the Playtest, as I made mention when I wrote that handbook, but the loophole was filled when UC came out, so you have to shenanigans your way to it unless your DM handwaves it or you become a Pale Stranger yourself for magic reloads (that actually bugs me quite a bit how the Pale Stranger just handwaves the entire matter with magic. ).