If it's a vertical 2x15 tall cab.
Duke from AudioKenisis has modelled it with an eminence as follows.
"My suggestion is the Eminence Delta 15A. A pair will give you -2 dB around 82 Hz without a midbass hump, and the efficiency and top end extentension are both rather good for a 15." http://www.eminence.com/pdf/deltapro-15a.pdf
You could sell a couple of the vintage drivers and have change.
These cabs are not enough internal volume for making best use of the EV 15L's as infinite baffle designs. Well I use the term design very loosely.