7 1/4 with 3:55's or even 3:23's

You can still get the 3.55 & up gears from the aftermarket, and even some factory ones may be floating around, since Mopar used a 7.25 in the front of the 4×4 Daks early on.
SGs are a bit rare & parts are almost nada.
Nobody last time I checked nobody is making the 3.23's tho', I have (2) sets of OE ones, and (1) NOS set of 3.55's. The SG I have is a later style with a solid carrier, vs the older 2 piece/4-pinion units.
@Charrlie_S has listed the whole range of race gears available back in the day.