Advantage Grip's 'EZ Travel' breakdown 4x4 would be my suggestion.
I bought the kit, & supplemented it with some additional diffusion, & floppy, 'slippers, plus a third frame.
Bought the bits from Adorama, & BarnDoor Lighting Outfitters, as their prices were less than listed on Advantage Grip's site. Might be worth contacting them directly as it seems many Grip companies sell their wares below list.
A breakdown 4x4, & floppy slipper costs about $185 before shipping.