I'm pretty sure those are from a late 60's Sunn Coliseum PA system. If so, the 215 cabs were loaded with JBL D130's and the drivers behind those radiators were probably JBL 375's.
Sometimes referred to as a "Beach Boys" PA because the Beach Boys used the first ones in the mid 60's.
Pretty rare stuff. Not many of those made, no frame of reference really so it would be hard to even guess at their value.
Fairly useless as far as live sound in today's world, the only interest might be from a collector, or more probably a vintage hi-fi person interested in lust the drivers themselves.
If you still have the 215 cabs, those D130' are worth something if you find the right person; as with the horns, vintage hi-fi folks, however if they are solid there might be some interest among guitar players.
If you want to sell them, put them on eBay. You'll certainly find out what they are worth that way.
If it is indeed a 60's Sunn Coliseum PA system, and you happen to ALSO have the amplifier that was used to power that system, that's another thing altogether. Those bring pretty strong money from the musician world.