Many years ago the now-defunct Lafayette brand (kind of another Radio Shack-type company) carried the tweeter in their top speakers. I believe it was in the "Criterion" lineup from that brand. The most successful incarnation, though, seems to have been the ESS company's models.
I've heard mixed things about the new speakers, some of them not terribly flattering regarding the durability of the current tweeter units at higher volume levels, and the sound at the crossover region. As usual, it's up to the listener...
Bluenose is right, however: it is VERY tough to mate that wonderful tweeter to ANYTHING dynamic.