Brass hinges on our '84 have pins that are intended to stay in place, but some don't. One dropped out and disappeared prior to our ownership. Relatively cheapie brass hinges I've bought for the kitchen cabinets are similar and similarly disposed to lose their pins. These pins stay in place only because of the interference fit in the barrel of one leaf of the hinge.
You should not have to drill the pins out. Take the hinge off and to a place you can firmly clamp it. Then drive the offending pins out. Normal collections of store-bought drifts do not have long enough cylindrical punches or drifts. I use common nails of the largest diameter fitting the barrel as my drifts; I grind the point off so that the new drift does not spread the pin wider. (My drift, punch, and metal chisel collection has quite a number of repurposed nails.)
Finding new pins can be a chore and luck plays a part. I've used brazing rod. Either snug one of the barrels, squeeze in a vice or tap it slightly out-of-round or slightly flatten/widen one end of the pin to hold the pin in place. Make sure the other barrels are loose enough to allow the hinge to operate.
There's no drilling the pins out that's not fraught with frustration and failure.
