The 2 speed kick shift hub would be your only option? it feels pretty naff compared to a nice track hub with a nice freewheel, plus you could just change your gear ratio if you're climbing
There are a number of other options. Mostly 3 speed Sturmey's though. But they've got a decent range and go for ages with little to no maintenance. Its not a bad option but I always found the gear jumps way too big and the drive feels clunky compared to single gear.
I don't think you could fit that onto a Dolan FXE without some bodged up cable guide, the 2 speed has no cables so would work, still wouldn't recommend one over a normal hub though, just flip the wheel
The 2 speed kick shift hub would be your only option? it feels pretty naff compared to a nice track hub with a nice freewheel, plus you could just change your gear ratio if you're climbing