Sandwich white mill rural heritage centre

Some good progress on powering the old lathe over the last couple of weeks, the motor is now mounted on the wall behind the lather & the layshaft is mounted under the floor above... It all rotates smoothly, the home-made wooden pulleys are surprisingly concentric!
The motor is now mounted to the wall behind the lathe & connected via a single vee belt to the pulleys previously installed under the floor above the lathe ... All seems to run smoothly when the motor is switched on.
The next problem to solve is what to use as a drive between the layshaft & the lathe... An old leather belt? A piece of seatbelt webbing?