If it's for upholstery, then it may be on the thick side, unlike your garments. you can make a pieced top, but I don't think you are actually going to want to quilt it. It will weigh a ton. I made a couple of covered pillows. I cut the leather exactly to size, butted the edges together and zigzagged them together over a piece of muslin. I used a leather foot (see if you can get one for your machine) and a leather needle.
If you are still interested, I would order a small amount, even if it's a premium price, or maybe he can send you a sample for a few bucks.