I am sure that we have a belt available for that scooter. If you still have the old belt can you see any numbers and letters printed on it?
These numbers and letters may be placed together (5355M15), or they may have dashes and or forward slashes between them (535-5M/15), or they may have the first 5 digits only (535-5M or 5M535). Other variations are also possible depending upon the belt manufacturer.
If the old belt does not have any printing on it then:
With these measurement I can match up the right belt size for the scooter.
Regarding putting a larger 200W-300W motor in the scooter. That is possible and would be a good project. A 200W-300W motor would be larger than the original motor though so modifying the frame where the motor mounts to it might be necessary. A larger motor would also require a wider belt to handle the extra power, or switching over to a chain, and finding and attaching the corresponding sprocket to fit the rear wheel. It is really an in depth project to install a larger motor but if you like that kind of challenge then it would be rewarding.
I own an e-scooter of a Homcom Deluxe Electric E-Scooter 120W Motor 24V (link here), it had been working nicely so far but its belt just snapped today. Now the engine is not connected to the back wheel anymore. So I would like to buy a replacement for the belt, but have no idea which one is for the model. Anyone can recommend? Thank you very much in advance!
Oh and another question, is it possible to replace the motor to be more power, say, like 200W or 300W. If so, how would I do that?