I was thinking it wouldn't be too far of a stretch, to at least see them with some sort of aerial vehicle nowadays. Balloon corp. or something similar, to be more specific is what I was thinking. Balloons were used in some wars, decades before the 20th Century rolled around, mostly for observation posts, but there have been times where they floated over the enemy and tossed grenades out of the basket. It wouldn't be too big either, as it probably wouldn't be too popular of a place to be assigned, and they might not have too much of a use for ballooners checking out places?
What about a navy of some kind? Could the NCR have a NCRN, New California Republic Navy? Maybe they brought back the Age of Sail at the very most. I was thinking it would sort of be amusing to see a NCR Navy, sailing around in none other than something that resembled (or was simply just a reproduction) of those Chinese Junk boats. And seeing as the Shi might be absorbed into the NCR, their possibly passed down through the generations knowledge of ocean going, could have come in handy with this point. Again, like their balloon corp., it wouldn't necessarily be all that big.
By the way, if you're wondering where I pulled these ideas out of, I just started thinking about them after thinking about those NCR cavalry soldiers in the Fallout: New Vegas comic prequel, and wondering what else the NCR might have.
So what are you ideas, and what might you have to add to what's already given?