I just pulled the headliner out of the Buick and the headliner board is not reusable. It crumbled to pieces. It looks like it was out before. Anyways....
I've never heard of anyone selling these. You/we may have to find a used one out of another G-body. For example, I figured the one in my '81 grand prix would fit and or work fine, but I haven't tried yet.
Any Gbody headliner will work from the same years body style.Just make sure the over head dome lights are the same.Moon roof Gn's can be taken from Olds moonroofs.There seems to be alot more Olds in the yards then Buicks.