restoring an old moped that set for a while

my mother had a suzuki moped FA50 1985 model and she quite riding it and it sat up for years in a barn and i got it and started working on it about 15 years ago but i was afraid to take to much apart because i didnt want to mess it up so i gave it to a friend to look at and he noticed that the piston was broken and he took it apart and lost some peices and i lost the head but i have the top of the head just not the piston shaft

i have missing from it

the throttle cable

head

piston

right break cable and handle

and all the electronics on the right side the plugs are there jsut not the componets

and the instrument pannel i have the box just not the top where the speedometer and igniton are and once again the plugs are there

the engine cleaned up real nice and turns over real smoothly and looks great

but would someting like this be good to restore and how much are we talkin about spending here

i would be fine with used parts