the vacuette belt on the left is slightly narrower & is thinner than a regular kirby belt.the vacuette belt is slightly less than a half inch & the regular kirby belt is slightly larger than a half inch.
A Royal style 2 belt might work. The style 2 belt was meant for the broom vac series. I would soak the belt in hot water then try to fit it on the vacuette. Hope it works,
-Jack
The Kirby Vacuette was also sold under other names:
Douglas Busy Bee
Douglas Aardvac
Oreck
Kenmore Klean 'n Vac
Craftsman Powermate
Sew-Rite Sew-Clean Vac (Tacony)
The belt you want to find was also used on these above models.