I thought they started making Wagons in 72?

As far as I know, '72 was the initial model year. However, many were built in 1971 (probably after the '72 model year production begins in late summer) and most likely could have been purchased in late 1971.

Lord, I am going to date myself with this one.
Back in the "Good Old Days", new car models were generally released for sale in mid-September. It was a big deal to see all of the ads, and to visit the showrooms to see next year's model. Production of, for example, 1972 models, generally began in about Late July or Early August, and the cars reached the dealers about the first week of September, but weren't displayed until about September 15th, or so.

As a kid, I would hit all of the dealerships along N. May Avenue in Oklahoma City, (Dub Richardson Ford, Nip & Van Rambler, Lynn Hickey Dodge, etc.), and fantasize about owning a new Mustang, or AMX, or Challenger.  Didn't we all do that, at one time or another?
But that all changed in the early 90's now they release new cars almost a full year ahead, i.e, 2005 models released in January or Febuary of 2004.  That's just dumb, IMO.

Ah, those were the good old day, when men were men, Fords were hot, and Chevy's bit the dust.

I looked at a Pinto one time about 10 years ago and I remember it having a build date of November 1970.