My guess would be Sand FS33531 / Dark Tan FS30219 / Brown FS30118.
Let me find out for sure though. Just an FYI, Fightertown Decals recently released a large USN Adversary decal package with the sister aircraft to the one you are doing on it, Red 23. Looks to be done in the same colors.
That first combo might be a bit to dark. This may work better FS 33531 Sand, FS 30400 Tan, FS 30219 Dark tan. All these colors should be available in the Model Master, and Vallejo lines, not sure about Gunze.
Here is one last color combo, and the one that makes the most sense. Got these from the color chart of the AFV Club F-5E kit, FS 30117, FS 30279, FS33613. these would be the colors used on Red 23 according to AFV Club.
You may have to mix a few of your gunze colors to get the shade you want. If your a member of ARCAIR.com or the Hyperscale.com forums, Id suggest you ask over there if anyone has a good mix ratio for these shades.
I was going thru a few paint guides online. VFC-111 had an aircraft in a similiar scheme and its one of the markings options in the AFV Club VFC-11 F-5E kit... They list these colors for it, Gunze Hobby Color H-318, H-27 and H-37.
Ok I can help with this. If your doing the jet in the picture. The colors are 30140. 30279 and 33475. If u whant to make the color mix a 9 to 1 of radome tan to military brown. But if you whant the pinky ness of the color than look at the Testors square bottles and match the pictures