sub enclosure?

It depends on the woofer. It may be able to use a one cubic foot box with a port or it may not. The only way to tell is to drop the Thiele/Small parameters into a software program and see what happens. Set the box size to one cubic foot and then play around with the port tuning. It may work and it may not. Ported boxes have a theoretical volume increase of 3 decibels over a sealed box. This usually means you'll need a larger box though. The port, when design properly, will reinforce the lower bass up to the point of the port tuning frequency. Below the port tuning frequency the bass will drop off rapidly. My gut tells me that box is too small but you'd have to run the numbers to know for sure.