Power brake conversion

[C15_Sierra]

I want to convert my '80 with manual brakes over to vacuum power brakes. Do I need to swap a vacuum power brake pedal as well, or can I get away with my manual brake pedal for the time being?

I've also been looking at auto trans brake pedals - truck was originally a 3 on the tree - because when the truck was converted to a TH350 some time ago, the PO just took off the clutch pedal, so it looks kind of awkward with the small brake pedal. I'm wondering, is there's a difference in hydroboost vs. vacuum pedal ratios?

Thanks!