You are in LA
is there still a fall fling at Woodley park, Long beach and or Pomona swap meets, advertise in the wanted sections
a little patience will score you a manifold
find some exhaust flanges and check out the ford headers
Poly uses shorter cam than the LA for the same torque curve - solid or hyd- your choice (is this year dependent?
post up your compression, gears, converter, usage, weight B4 thinking of a cam change
IN LA I'd talk to Engle first but Mopar grind not chevy
Else Bullet, Ultradyne for solids, Lunati RAcer Brown
IDK if Oregon has any Mopar masters- here in LA you could get a chevy re grind from Isky or Clay Smith, Chet Herbert has some mopar profiles
good core is what to find first