I have duckies with the drop stitch floors too. I got a k-pump 20, for the dual stage pump. Not too big, and works great as a top off pump for the duckies..
I also have a couple inflatable paddle boards that I use it on. It is actually a pain to get them to the 15 or 20 lbs with the kpump, so I made an adapter for a portable tire inflator/compressor, which is nice because they can inflate while I work on other things.
But, yeah, for traveling down river, the kpump 20 is great., or maybe the 220 if you wanted a larger one, which I don't think you do.
"If I'm not there, it means I'm dead...or late!" General W.R. Monger