Yes - but probably not good for a stock restoration.
I've used the 3rd seat out of a Chevy Suburban from 92-98 with great success. It folds down for access behind and, if you mount it as it is mounted in a Suburban, it will also tilt up towards the steering wheel leaving you easy access to underneath. An 86 Mazda MPV 3rd seat is also a near perfect fit (I've got that for a 40 p-up I'm building now adn I've matched the leather upholstery with some really nice vinyl I'll use for the rest of the interior).
Mount the seat using the top back portion of the seat just under the rear support, underneath the rear window, and set it up against the back wall of the cab, making your seat mounts about 1/2" higher in the front than in the back (for good thigh support).
I've posted a pic of a truck I did awhile back as a reference. Upholster it to choice or, if it's clean, match material to your seat and do your own interior as I did.
If interested in more pics, PM me with your email address and I'll send you a link to some additional ones.