Try Great planes who is the distributor of Kyosho in US.
Not sure if they are going to import them.

You may also try singapore hobbies. Since it is smaller than Flip 3D currently available in US, the shipping cost should be low enough to buy.

Or, you can order from http://www.hobbynet-jp.com
Mr. Hiwada does good job there.

However, If not available in US, Singapore is cheaper because no export tax.

FLIP 3D 25 Technical Data
Length 1,250mm
Wingspan 1,240mm
Total Weight approx. 1,400-1,500g
Wing Area 42.0dm2
Wing Loading approx. 33.3-35.7g/dm2
Airfoil 20% symmetrical
Engine(not incl.) 2 stroke 25 class
Radio(not incl.) 4 channel 5 Servos