new engine for 72 trailhopper

[chaserr]

I have just bought two 72 trailhoppers and one of them is missing the engine, I plan on keeping one of the bikes original and have fun with the other. So i was wondering if anyone knows of a more powerful replacement engine i can get for the bike?

 

[clonebuilder]

if u got to the website called tboltusa.com u can get some powrer full engines for a good price