Sorry to burst your bubble, Fred, but I did that not long after I started leatherwork. I started off making holsters (no messing around for me, straight in the deep end ) and used a Singer 201 domestic machine to pre-punch the holes. I could only do one layer at a time and it took a bit of juggling lining up the holes but it gave me nice straight, evenly spaced holes for the awl to go through. I made a few holsters and gunbelts using that method.
SUP, hand-stitching knife sheaths obviously won't be as fast as using a machine but they are relatively easy compared to holsters/gunbelts AND a saddle-stitch is far superior to a machine lockstitch. There is something intrinsically satisfying about hand-stitching a product but once you have to charge for your time you are in trouble as very few will pay the rate required. As long as it's only a hobby you can get away with it, in my case I covered my material costs and made a bit extra but I made them for fellow club members so wasn't concerned with getting the going rate for my labour. My wife said I'm not very good at charging for work I do.