I have the speakers I grew up with in the 50's 60's.

Jane- The problem you are having is likely a result of some semantic challenges.  The James Lansing 375 is a "driver" or individual speaker that covers a portion of the entire sound range.  It was used in professional theater type and PA type systems, as well as (less frequently I would imagine) in home applications.  As mentioned by mechans the active part (driver) usually was attached to some kind of horn or acoustic lens to project the sound.  In a home system like you apparently have, it would have been mounted in some kind of cabinet with the lens or horn inside (maybe visible from the outside, and there is probably a large low frequency driver or woofer also in that cabinet.  If you can post a link to a picture of the front and back of the speakers, you can get better information.  Given the age, and the variations in mounting and etc, you will not find a reliable bluebook value.   Also condition and location will affect value, since they are probably large, heavy cabinets and shipping will be expensive.  It will likely require an auction with very thorough pictures and documentation to establish a true value. Given that they are collector-type items, with a world-wide but limited appeal, you will probably want to reach the largest possible audience when you choose an auction site.  

Janet. Contact me, I can help you. 865-three zero four - six nine four sev

will call later.  i am 409 457 4527 in Texas

late and not certain where you are although 865 is central.  will try you tomorrow.