If your going to go with ONE, and possibly a second one, I think the sb3k might be the best choice. It seems like the biggest obstacle for you is size(and maybe still holding tight to the sealed is tighter thing). So despite my earlier suggestion(and Ryan’s) I am voting sb3k BUT keep in mind I’m saying that while thinking of the SVS app to help control it. I imagine you’d try it in the original location which as we’ve covered, need some dsp.
I noticed you mentioned the PC2k was too tall. Two of my subs are pc12pluses and are 39” high!!! Can’t even see em...lol
Just shot this as I was typing.