In case anyone is interested, I spotted two center-mount turbo 6.5L's in small school buses at Buddy's Upull salvage yard in Springfield, MO today:

http://buddysupull.com/

You have to pull the engines yourself, but they are cheap! The price list online shows diesel engines for $360 plus $110 core charge.

I don't know anything about the condition of the engines, but they looked complete.

Casey