Do your c-stands have the detachable base? You could put the bases in one case and the long skinny parts in another as the cases made for c-stands are $$$$ and heavy as heck.
Can you rent at your destination? It seems like a real PITA to ship C-stands across the country.
Yeah, really - renting at or near your destination is always a good idea for grip. Otherwise use lighter-weight stands...I've got a few mid-weight Impact or SP Systems stands that are maybe 1/3rd the weight of a c-stand but still pretty sturdy.
You could use something like this to ship or fly with grip gear:
