Oh there are plenty of places to get parts. If you get a 50cc, you'll have a GY6 139QMB engine. If you have a 150cc, you'll have a GY6 157QMJ engine. These parts are a dime a dozen for standard replacements and can be found at dozens of different interenet dealers.
Scooter Parts: Chinese and Asian Scooter Parts, Wholesale Scooter parts, Parts for Dirt Bikes, ATV, Off-Road Kart Parts. is possibly the most reputable. Just type those engines into google and you'll see what I'm talking about.