RE: Dumas Creole Queen paddlewheel belt.
Suggestions for belt:
1. use a knotted string as a temporary belt to find the correct Dumas belt length; use several wraps if you need more friction with this temporary belt. Or use a rubber band, though length measurements would be harder with the stretchy rubber.
2. What is the belt made of?
3. You can CA the belt ends together,
or sew them (traditional way to join ends of a rubber or leather belt),
or use a staple, if the pulleys are large enough with a deep enough V to pass the staple.
4. I have some semi stretchy, round, plastic/rubbery thread that might work as a belt for a V pulley, try the sewing stores in your area.
5. install a spring tensioned idler pulley to take up slack in the belt, making precise measurement of length unnecessary.