Flatacraft used to make the handles themselves.
I made some in the past exactly as they did with some offcuts of Hypalon and some 1 inch webbing.
The webb is doudled up and stitched together, except for a couple of inches each end. The ends are then pushed through a slot in the middle of the hypalon circle and the two pieces of webb splayed out and stuck back to the back of the hypalon. When dry the hypalon circles are glued to the tubes in the usual way.
Don't forget by the way to seal the ends of the webbing with a match.
I understand the gluing method will be new to you at this stage, but you can practice getting a good join using the bits cut off when cutting out the circles. Just get some good quality Hypalon glue with catalyst and follow the instructions on the tin.
Shame your not closer as I'd happily show you how to do it so you can learn for the future.
RIBBED For extra pleasure.
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