See what you mean; I noticed the delivery time for these is about a month... not so great.
Maybe I could make my own? is it doable with veroboard, and a gang of opamps with a gain of, say 1.5 to act as buffers? Opto couplers on all lines except step/ dir... I can solder okay, what spec amps and optocouplers might be okay? Or am I heading towards noise problems, too? Could noise be negated by mounting the Bob(s) as separate boards, each very close to my drivers? Loath to spent more on electronicky stuff than I have to. Maybe shooting myself in the foot, of course.