1974 princess auto bike, engine and shock help

Hey Gang.

I have a 1974 princess auto minibike, its all original.
a few questions, I believe it has a period correct 3.5hp briggs and stratton engine. with the pulsa jet carb

1) I need the spring that goes from the throttle tab on the carburetor to the rod that goes behind the engine shroud (the rod that has a little loop on it) I currently am using fishing string but I am positive this is bypassing the governor.

2) on my front shocks, I had to disassemble them to straiten them out. I noticed some plastic sleeves that go in the upper portion of the shocks, I suppose to help with friction, where can I buy these? mine are torn and are not working. the ends of my shock tubes (the portion you can pull out and are chrome plated) are very badly worn on the tops from being used without the wear sleeves.

3) can I get airfilter housings for this engine?

[YOUTUBE]MiniBike : Princess Auto 1974 - YouTube[/YOUTUBE]