I have a pair of 911 seats for sale and I think 400 dollars for the pair is fair. I installed them in my 914 and they fit save the height issue created by the seat sitting proud on the seat rack.
I am 6-4 so that doesn't work as the relationship between my (balding) head and targa top was costing more hair than the seats are worth.... around 400 dollars or 40 dollars per follicle.
These are full leather manually adjustable and can be adapted to a 914 or fit a 911 as-is.
The leather exhibits the patina of many spirited encounters with Southern California babes and may need to be reconditioned with one or another of the crèmes available in any local car detailer retailer shop.
I will post photos if necessary or I can continue to opine as to the surreal experiences that await you sitting on these legendary hides.