ernie.
you can get new ones from john sherman at volks conversion up your way if you dont have any luck with finding a used one.
Ive had a ea81 in a 75 bus, it had the radiator in the rear with a big hole cut out of the engine cover with mesh covering it to let air flow.
Luckily it had a temp gauge installed so i could tell when it was getting too hot an could slow down or pull over for a while.
http://www.volksconversions.com.au/contact.html
Hope this helps you out!
cheers