The rubber boot and black plastic cover are available, Airspeed can get them. If you are doing a complete dissassembly, you must use a new rubber boot, they are less than $10.
For the wire, use an old VW heater cable, it is the same dia.
Be careful rechroming the trigger, it is pot metal and the polisher guy will very likely polish off the detail in the \"HURST\" lettering. On the bright side, (pun intended!), you will be able to polish off the flashing that runs down the middle of the trigger. My recommendation is to get them to handle the chroming of the steel shaft, while you should do the polishing of the trigger. Get them to strip the chrome, then start sanding.
When you have it all apart, you can tighten up the play in the white nylon bushing halves by sanding the mating faces on sandpaper on a piece of glass.