The 750 was introduced in 1977, had an AGO 32-note pedal clavier but I am uncertain about the transposer. It should be pretty obvious as the pistons are there in the rail below the upper manual.
I have the 725/750 service manual for sale from my collection @ $14 + shipping. If you have other questions or concerns, feel free to contact me off-Forum a <email@example.com>
. . . Jan