Before the grass grows too high, you can give it a quickie cut by leaving the VR out of the tractor - insulating the wire ends - and running the tractor off a fully charged battery. To be certain nothing grounds the field terminal on the starter / gen, you may even want to temporarily disconnect the wire off the "F" terminal of the SG motor. That way, the field wire cannot accidentally make contact with ground and turn the SG motor on full charge.
If your battery is in decent condition, you will likely be able to get in 60 to 90 minutes of run time on a full charge. At least you can get the first inch or so of grass taken off! Recharge the battery and cut the other inch or two later this weekend.
The VR maybe able to be repaired by drilling out the rivets on the shock absorbing brackets and replacing the sheared rubber with a suitable replacement. I have used rubber mat material from horse stall mats or rubber carpet runner mats stacked and super glued together. Drill and re-rivet.
Assuming you have any interest at all in fixing versus replacement of the VR, I would first inspect the relay contacts on both relays. SEVERE pitting or material transfer may ultimately cause you to replace the VR instead of experimenting with it. Small pitting and material transfer can be addressed but remember, better VR units have a thin tungsten coating on the relay contacts. If that coating is gone, reconditioning the contacts is only a temporary cure.
Once you have the lawn lookin' good, if you wish to continue trying to save your VR unit, I would be happy to help.
As a quick tip, if you rewire, use MARINE GRADE tinned wire for the project. I have purchased wire from a dealer in PA. that sells by the 100 foot length - but allows to choose how many feet of each color you want in that total of 100 feet. So if you want 20 feet Red. 20 feet black, 20 feet yellow, etc, you can get exactly what you want / need. The wire is superb quality with a thick insulation covering. Being new here, I don't know if I'm allowed to mention the source, but you can always email me.
Chuck