I made a note once that the 아/어 있다 construction can be used with 가다 and 오다, but I can't easily find any example sentences. With 가다, would that be written '가 있다' or '가어 있다'? Would it mean that something "Is still away" (having gone)?
가 있다 is definitely possible, it can be used to mean that someone has gone somewhere and is still there right now.
Same with 와 있다, it means that someone has arrived here and is here with the speaker right now.
Examples:
엄마는 지금 미국 가 있는데. Mom is in America right now.
저리 가 있어라. Go over there and stay there.
여기 안 와 있는 사람이 누구지? Who's not here right now?
우리 집에 와 있지 그랬어. You should have come and stayed at my house.
Note that 가고 있다 and 오고 있다 is completely different.