Spring & Cable
Probably best to get the spring from a place that can get parts for a Honda 120 engine. Govenor springs are very touchy when it comes to the right tension to make the engine run right. If the brake cable is just frayed you should be able to replace the cable and not the outside covering, if your handy go to the local hardware store find the right size cable, remove & resoder the handel bar end on and replace cable. If not so handy some motorcycle / sled shops can fix you up with replacing just the cable. Hope this helps.