I want to send my Graflex 4x5 to a professional to attach a rangefinder and calibrate it to my 150mm lens. I tried sourcing and calibrating one in the past, but I quickly realized that I'm better off just pressing the shutter button . Family portrait sessions feel like hardcore sports photography because my subjects are incapable of sitting still. I can still achieve critical focus without a rangefinder. Having one would make my life easier, though.

Who would you recommend?