The pontoon skin delaminated on my Outcast Discovery 8 pontoon boat, but the bladder is used but still good and airtight. The actual bladder length is about 9 feet, but it is intended to fit an 8 foot pontoon and should fit Outcast 8 foot pontoon boats of that era. You need to compare the part number shown in the second photo to make sure it will fit your pontoon skins, as the various Outcast models have the valve placed in different locations. I'd prefer that any buyer see this bladder in person to make sure it will fit your pontoon skin. I live in Kent East Hill and I'm retired, so generally available unless I'm gone fishing or golfing. PM me for my address and phone number. If you've never replaced a bladder, be advised that trying to get the pontoon skin to fit around the valve seat can be a very frustrating experience; I found that if I used some dishwashing liquid to provide some lubrication, it made the process a bit easier, but it is still not easy.
Rex