OZ Bonneville.
I don't know what kind of questions you have, but I've owned my Bonneville since 1979 (new). Ive been trying to find a set of front seats that tilt, with no luck. I'm tired of looking into the stars when I drive. I would like to see whats ahead of me. I have given up on locating anything from a 79, bit I'm looking for anything that will fit my ride.

Is it possible your seats could be repaired?
I suppose you have called the Junk yards, but I'm wondering if one of the trim/upholstery shops, or even body shops may know someone that might be able to fix your seats?

Try this site.
Car-Part.com--Used Auto Parts Market

I see a left and right seat at only one place, says it is blue..

1979
Seat, Front
Pontiac Bonneville (1979 Down) LEFT 40-60 BLUE NICE DJ0658

1979
Seat, Front
Pontiac Bonneville (1979 Down) RIGHT 40-60 BLUE NICE DJ0658

A-1-A Auto Parts, Inc. USA-FL(Lakeland 1-800-922-9676
A-1-A Auto Parts, Inc.
Quote Request Form

I replaced my 60/40 front seat in my 86 with some 98 bonne buckets. 50 bucks the price was right, drivers was 6 way power to boot. Way more comfy .