One other comment. What you need is the clip which attaches to the hand support. The other pieces can be made/purchased through a leather supply outlet.
Could not find at any of the suppliers a couple years ago. Found the "z" hooks on ebay and made my own leather belts. Tandy leather has buckles and sells leather straps along with dyes. Made all leather belts for Roadster, including trunk belts - so they all match
The "Z" hooks are available from Snyder's. I purchased a pair not long ago. My invoice shows the number of A-42137-S, which does not show up on the inventory. Try contacting Joe at Snyder's for help with the hooks. Try looking on Amazon for a kid's belt. My belts are just under an inch wide and about 16 inches from end to end.
Thanks you all are so helpful. I re-discovered the straps- they weren't lost after all. My beautiful green car was the star of the Saint Patty's day parade in Greenwich CT a couple days ago. Brought a smile to many faces young and old.