The 24-year-old has not featured for Rangers this season and has spend much of the last few years loaned out to other clubs to gain experience.
Former England Under-19 international Ephraim was linked with a move to New York Red Bulls during the January transfer window but remained in west London.
Now the ex-West Ham trainee knows he may be forced to leave in search of regular football.
“Promotion was a great moment but to be honest I haven’t had many good moments since,” he told talkSPORT.
“I just want to go somewhere, play some games and get a smile back on my face.
“I’m a London boy and playing here is great. But whether it’s in London or not, or abroad, I just want to play and move my career forward.”
Derby's decision to postpone Sunday's home Sky Bet Championship game against Cardiff was made independently, Derbyshire Police have confirmed.
Rochdale have no new injury worries ahead of Tuesday's Sky Bet League One relegation battle with fellow strugglers Fleetwood.