TMI should make them, or can as a special order.
Cushions are not the same due the '68's being two post and the '69 single post. They were cut differently to accomodate...
You can pretty easily adapt the '68 set back to take a '69 headrest, the 69 rests are reproduced and of pretty good quality if you are not after 100% "correct", and the original 68's are really hard to find...