I have some info on this at home. I was just going through my Speakerlab papers last week. IM your address and I'll copy the appropriate parts for you.
Speakerlab, back in the 70's and 80's, had some modestly priced kits and factory built speaker systems. They were very well designed, and the drivers chosen were either made to their specs, or cherry picked from other manufacturers.
They are still in business today, but make just three kit models apparently aimed at the HT market. One is a small bookshelf or satellite type, another is a pair of 2-way towers. The remaining model is a center channel. The store appears to be a full line stereo/ht shop, and the Speakerlab kits just some "store brand" speakers.
Some will tell you that the Speakerlab K Horn, which was essentially a modified Klipshhorn, was misdesigned in the throat area, but they had specific reasons for that, and it is explained in one of the many papers I have from them. They also describe woofer requirements for large corner horns.
They sold plans as well as a few factory built K Horns.
