Boy, that's a tough one F4. Currently to my knowledge there is little that is available now as for current production. But there are a few options that I am aware of.
One's that come to mine are. House of Balsa P-51 that is rated for a .049 but, a .15 can easily be fitted into it and fly's nice. Currently HOB is not producing kits, but, "they say" there going to start production soon, What does "soon" mean?, well in my experience with phone calls to them, they have been indicating "soon" for the last 2 to 3 years. There is always E-bay and R/C forums, swap meets avail though. Other options are the "Airkill Combat Planes" that is currently being made available by the original manufacture. httphttp://www.rccombat.com/sections/man...s=129&Users=34
The reason I say this, is that myself, I just completed a 1/12 th size Bearcat racer with a .15 that we fly in local club racing and I believe it is a nice product.
If your looking for say, a fiberglass fuselage and foam wing kind of kit, I am not aware of any current production. Pretty thin pickin's out there. Other than scratch building or building from plans, which there are a lot of options out there, say, Model Airplane News Plans, Model Aviation plans thru AMA, and the like.