I recommend two or three subs. Rhythmik F12 or the bigger dual sealed or F15 would be great in that space.
I agree with those that say maybe tower would be better. Some used tektons could be amazing for that space. Like used moabs or double impacts. Could get new but some people don't want to support them after the battle with Erin at Erin's audio corner. Otherwise keep an eye on Perlisten or Arendal monitors/smaller towers!!
Best of luck to you!!

