I always loaded mine rear first to get trailer weight distribution right. If you load front first you may not have enough tongue weight and trailer will be squirrely. An electric winch works great, but you do have to get the car lined up straight as you won't be able to adjust the steering...
A UK company called Nova acquired the machinery and rights to manufacture Avon tires. They have indicated CR6ZZ tires for Cobras and GT40's will continue.
Don't think the site is gone. Frequently there are temporary shutdowns or difficulties in bringing the site up. This has been going on for a few years now.
Agree that the repair is worth a try. I'm not optimistic you're going to get the balancer off and back on with SPF clearance. Also towing the car and having the engine removed is way more complicated.
I would agree with Lee's advice Mike. Yes the waterpump can be removed with the firewall off and serpentine belt removed, but best to determine what if anything is causing overheating. Weeping from the waterpump would not cause this,