Help finding replacement driver

I have a pair of Green Mountain EOS that I just upgraded with RAAL tweeters using RJ's crossover specs. I am very happy with the results but . . .

I am wondering if I could find a replacement woofer that would be an upgrade in performance (without having to completely redesign the xovers). The drivers are not labelled so I can't find specs for them. the tweeters were about 5 ohm 92 db.

Anyway, maybe I am being naive that I could find a reasonable alternative. Anyway, thanks for any opinions/suggestions you might have.