Summit brand exhaust kits
i know it's not an A-body but fwiw I use a 2.5 inch Summit kit with mufflers on my '68 Coronet. The tailpipes all fit pretty nice but had to modify the front of the system to connect to the Summit headers - apparently the system is designed for Hooker headers. Still came out nicer than I'd have got from a muffler shop for that money.