Just a quick question; why don't you build your own?
I built my own for my sub simply because I needed a 3+ cubic foot box and I had serious space constraints.
It wasn't 100% perfect as the place I took the MDF to get it cut didn't do it properly (look at the bottom of the front panel), but it sure does work extremely well with all the bracing and glue I used. Its unbelievable how loud this thing is, and I'm sure it will look decent once I get it carpeted.
This website will even tell you exactly what size pieces to cut and what size and length to make your port in order to tune to a desired frequency.
By the way, I also have an Alpine R12 in the Bonneville that used to be in the Regal, though its only a single sub. That sounded decent in a ported 1.25 cubic foot box.
2005 Pontiac Bonneville GXP - For Sale ----- 1995 Buick Regal GS(X) - L67 madness
2000 Buick Regal GSE - Stock...for now
----- 1987 Jaguar XJ-* V12 - 12>8