They may still have the cabinet specs available if you call them. Or, alternatively, tell them what the enclosure should be tuned to (low end in Hz) and how big (in cubic feet, internal size) you want it to be, and they can whip you up the dimensions and porting. Or, they used to. Probably still will.
The model number should be on the back of the magnet. Don't try to ask them for an "earthquake" low frequency tuning if it's a guitar speaker or something
