All great options on the table. There is a crossover available (model X01) for the B&C 8cx21 coax and runs about $60 if IIRC. Maybe we could get Parts Express to carry for a bit less? Or get Mtg90 to design a cheaper/better crossover, akin to what he did for the Minion.
Besides, the TS parameters for the B&C coax woofer are essentially the same as the B&C woofer in the Minion (8ps21)... we could use the same enclosure and modify the baffle slightly (get rid of the horn cut-out and center the woofer)....an BAM we'd be cooking with Crisco. (You fellas see I've given this A LOT of thought, I need cheap timbre matched, point source surrounds to match my Danley SH100s LCR which also use the B&C 8cx21!!!!). I'd buy 4-6 such surrounds speakers immediately !