Bob Baker at ABC Moparts has had some major problems getting his plastic molded products made for about a year now...............his only supplier dropped him in order to make less intricate parts in much higher volumes that would give the supplier higher profits with less energy (I understand that the other product that got the supplier going in that direction is walk in molded tubs that seem to be the rage in recent years).
Recently though, his supplier has had some mercy on Bob and has supplied some 1968 - 1970 model years seatbacks and lower molded shields so those may be back in stock soon and Bob is currently updating his site to show as such. Bob is also trying to focus on getting some of the fuselage C pillar interior moldings made but no certainty yet on when those might be available. I am also continuing to check with him on the 71-73 molded seat covers and he is still trying to get some of those as well but he told me he doesn't get many requests for 71-73 bucket seat molded parts.
So if there is something you really need he said you should try to call him and let him know so he can better guide his supplier on what to focus on in the near term. Apparently his site isn't working as it should so he is working on fixing that as well.