Everything appears to be authentic Mars to me although the beacon bases appear to be RB's mated to Skybolt domes. I have never seen a widemouth Mars speaker although I'm guessing it, too, is authentic given the red disk on the horn.
I'd say $800 to $1,000 on Ebay, maybe more. These Mars bars are EXTREMELY rare now, and while this one does not have the classic Chicago PD/FD configuration, it's uniqueness and authenticity should still command a high price.
I have some original SW-2 bases if interested, and another collector advertises on Ebay for the plastic inserts for the domes.
Nice find!