"I was a personnel clerk in the USAF reserve in 1972 stationed at Ellington AFB (same home base as Bush). We had "better" equipment than the TANG had. They usually got our hand-me-downs. We had 0 (zero) electric typewriters in the person el headquarters for the group.
I know this because I spent a good part of the day typing re-assignment orders.
All our typewriters were manual.
"
Interesting. I was also in the USAF, from 1965-69. Every typewriter I typed on was an IBM Selectric. Some had Cyrillic balls, since I had to type in Russian part of the time.
In the headquarters office for our detachment at Ft. Meade in 1969, there were three IBM Executive typewriters...the very ones that produce proportional spacing like this. They were used for all sorts of documents.
These memos are not official memos, to be disseminated. They're memos for this person's personal file...I suppose to be use to cover his butt under some circumstance.
I'm not saying they aren't faked. I'm saying that they could have been prepared using the equipment at the time.
BTW, the IBM Executive I used to use to typeset that little magazine had a couple of interesting characters. Two of them were a "th" and an "st" as upper case on the number row. They were smaller than the regular font and printed in superscript position. Very useful.