That bike could be pretty easily restored and or made pretty nice, if you wanted to put some time and money in to it.
Is it worth it? That is up to you to decide.
The parts you are missing are all available. The parts you have are decent looking and could be cleaned up and used.
I recently bought the "ultimate" "Holy Grail" "Unicorn" Arctic Cat mini bike...
1970 Arctic SSScat II ST, with 134cc 8 HP Chrysler engine from the factory. Actually, it might be a 10 HP from what I was told.