>> So 1.9oz gets me the unit + a USB cord to charge it, right? <<
Yes but it depends on what you need to do.
Here's what I will take on a week long trip.
SolarFocus Charger with Lithium AA batteries (1.5 oz for the charger and 1 oz for 2 Lithium AA's)

Camera Battery Adapter 0.5 oz (very cool alligator clip that adjust to fit most Lithium batteries for pocket cameras) My Olympus has a weird mini USB plug and the cable weighs 1.7 oz, so I leave the cable behind and use the adapter that came with the SolarFocus charger (smaller and lighter than the camera cable).

The charger comes with a bunch of mini USB adapter plugs that fit on the supplied cable. One fits my inReach SE and there is a standard mini USB as well so lots to choose from (each adapter weighs 0.1 oz and the supplied cable is .04 oz. – without any plugs attached)

I have a note in my gear list that indicates I have charged my iPhone from 16% to 100% with a set of lithium AA batteries however, I didn't note how much power was left in the AA's after the charge.
Good luck with your search and let us know which charger you settle on. I have to admit, if I was doing what you are doing I'd buy one of the 15 minute chargers and not worry about the weight (I guess it's a choice (weight vs wait))