As promised, an update.
Stock part did not fit. Seems that the hose wasn't the only thing missing, the nipple it attaches to was mostly broken off as well. So, my buddy's garage has a whole shelf system of misc parts from junk he's fixed for people over the years. We found some factory elbow/hose setup, that actually fit inside the stub (what's left of the nipple) as opposed to my $6 factory part sliding over it, and once we trimmed it to fit, we super glued the outside of it, and shoved it in the nipple.
Batteries are dead (not sure why) as I've worked on the truck to install the sound system and all the crap I decided I needed to go with it. Sound deadener is in, carpet is back in, RCA's and wires are starting to be run, so hopefully this weekend, I'll have it back together enough to start the truck, pull it outside, and crank the A/C on and make sure our homemade fix works.
Thanks all.