Well, what I'd do then is figure out what the cabinet parameters are then go to the online chat with PartsX. They've been very helpful when I've had sub design questions. They'll want to know the cabinet volume and configuration (i.e. ported (what size?), sealed, etc.) and how much power you've got. Then they can match the driver from their selection that best fits your application.

For best subwoofer performance you have to match the driver and the cabinet design. Otherwise you'll end up with an underperforming system.

There's also various free calculators online for sealed and ported subs that I've used in the past and gotten good results.

Note: I spend more money building subs that just buying them but it is a fun hobby and I can control the shape and color of the sub.