Purchased from an old line Honda dealer who stocked lots of OEM and high quality replacement parts in the heyday of Japanese imports but is now closed.
This is an OEM Honda Seat in very good to excellent condition. Pliable covering, Honda logo is very visible. The seat foam is old but not disfigured. Its cover is excellent with just two hardly noticeable 3/16" pinpricks pointed out in the picture and the seatcover underneath at the front there are two small slits shown in the pictures.
It has a rear hinge so it flips up to open. I have been told by knowledgeable collectors that it is a Honda SL350K0, and it is very different from subsequent years. However, please verify that fitment for yourself.