Board Thread:General Discussion/@comment-10993019-20140609202224/@comment-1824272-20140609205119

There's also the Dreamliner mentioned. If the F-15J hasn't shown up as an enemy NPC aircraft or as a parked aircraft in the background on the ground, then yeah it heavily implies that it may be available in the future.

The JASDF 309 Squadron does fly F-15C Eagles from what we can see.