Try 12 minute quarters. They work with any time of course. But 10 minutes is the lowest I could suggest from a simulation statistical point of view.
I think with 12 minutes you will still get great games and stat's. Once you start playing under 12 minutes you may not get the statistical accuracy you want if that is important to you. Also the flow of the game (momentum) is not as evident the shorter you play.
I would try 10 minutes. I get that you don't have an hour or an hour and half to play. I feel ya.
I am getting crunched for game time myself. Life happens.