My '72 was built 8/17/71 also, same as Super Blue 72. While I don't have a rally dash, it does have quite a few parts that are correct for a '71. All of my window internals are the earlier style, and some of the dash switches are the earlier type as well. It also has the 71 and early 72 style fuel tank, vs the 72-74 type. Other than SuperBlue I've found a few other early '72 cars with the '71 style rally dashes that are original to the car. Enough, in fact, that I bought a 70/71 rallye dash for my car for when I convert it to the rally dash. I'm not sure how late into the year this phenomenon occurred, but I do know it happened for cars with earlier August '71 build dates.
As far as the price goes, I bought my '72, non-rally, 318/904 A/C car for about 11k, and that was 2 years ago now (I doubt I could get that now). It ran, looked pretty much like it does below, and was my daily driver after taking care of a few minor details.