info about 1970's leslie stereo speakers

I resently purchased a pair of Leslie plus 2 model 450 speakers. They are from the early 1970's. I'm am searching for info about them, such as what they may have sold for new, can they be used as a two speaker system. I have learn that they were sold to be use as an addition to a stereo system to create 4 chan operation. The main speaker has two 50 watt amps built in them and each speaker has some type of a motorized baffle under a 15 inch woofer. Any info appreciated.
Sounds like you're describing a Leslie cabinet. They are designed to amplify organs -such as Hammond organs, like their B-3 and C-3 models. The motorized baffle is controlled by the organist -it has 2 speeds to create 2 different sound effects for the organ, and also spins the high frequency horn inside the cabinet. Just google Leslie cabinet.
the Leslie speaker is for electronic organs. At a relatively low power of 50 watts per, you apparently have some residential home type units.
The motorized spinning horn produces a doppler shift which sounds much like a warble tremelo effect, effectively raising and lowering the radiated fundamental frequency at a rate determined by the foot pedal controller (a part of the organ itself) which controls the motor speed. The Leslie effect is not applied constantly; it is turned on at specified times within a composition according to the musical score.
You may be able to resell them to a musical instrument shop or like minded website. As for any home audio use, I wouldn't know why anyone would want to do that as it seems an unlikely application. However I hardly claim to know everything; I could just be mistaken in ignorance. Might be some fun to play around with for special effects in a home theater setup. However again, I wouldn't think that you would want this effect to be on at all times.
The only Leslie speaker I know is being used in a studio in combination with an organ. It is really fun to see how the horn rotates and to hear the sound change with different RPM. Still no digital synth can reproduce many of the old analog sounds.
Here's a link to some info.