I'd forgo the vacuum pump, just because I think hydroboost is a superior system. A little electric unit with a small reservoir would operate the ac and cruise, so long as neither system is leaking.
I was looking at the piston style race fuel pumps,
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but couldn't find material used or compatibility to see if it'd work with diesel. It'd mount in place of the diaphragm style, and since most guys use big block chevy block off plates, I'd figure the pump should at least be close to fitting.