I started thinking....and that's dangerous..... I have a 13B-T alternator that's 24volt, and I either need to swap a 12v unit with the vaccum pump, or swap to a different alt and use my mechanical vacuum pump. Well, looking at the parts diagrams, I think it's possible that you might be able to swap the stator and regulator out of another alt into the stock 13bt unit. According to the parts numbers, a 22R alt internals are the same (but in 12v). I can probably find one of these in a junkyard for $15, so it's worth a shot.
The other thing I noticed, was that the 1985 pickup 2LT turbo diesel alt is a dead ringer for the one I have. The price isn't too terrible, so if the parts swap doesn't work, then I guess this is a fall back. Here's a link to the napa one....and one of them even shows the vacuum pump on there for right around $200.
http://www.napaautoparts.com/master...8292&Description=Alternator+-+Remfd+-+Premium
The other thing I noticed, was that the 1985 pickup 2LT turbo diesel alt is a dead ringer for the one I have. The price isn't too terrible, so if the parts swap doesn't work, then I guess this is a fall back. Here's a link to the napa one....and one of them even shows the vacuum pump on there for right around $200.
http://www.napaautoparts.com/master...8292&Description=Alternator+-+Remfd+-+Premium