Well, since you asked...

I would be very tempted to go the obvious route of AM882 (EM806 if you're feeling posh) plus the usual 45V toroidal-based linear power supply giving around 68V (off-load, anyway). Lower voltage power supplies won't save much money, and you can always turn max stepper current down to minimise heating if you don't need the torque. Frankly, I'm not too sure what other decent driver choices there are. Gecko? Over-priced and under-specced compared with the Leadshine drivers. Then it's down to the TB66xx kind of thing, which I've used happily off a 12V supply but which probably aren't fit for anything serious.

My philosophy here is to pay just a little bit more; in the long run you spend less by spending slightly more to start with than trying to minimise costs and wasting what you did spend when you replace it with the right kit. Different if you are manufacturing many-off. I remember a quote from somewhere along the lines of, "Pay a little too much for a tool and you forget the cost the first time you use it. Pay too little and you regret it every time you use it."

YMMV!