I have an 8600 with Accelerate G3/400 and a plain 9600 with 604/350 I think.
OS 7.5.5 would be quite interesting as well as a cd of 7.6.1, especially if you have an AV version of the OS for my 8600 which has AV hardware without proper software for it.
Same goes for my Macintosh Quadra 840/AV.
I take the offer of an ISO image as offer for the 7.5.5 as 7.6.1 would be illegal and should not be offered on this forums. ;-)