Keep in mind the length of the swinging part of the swaybar. It's about a foot on A-bodies (which BTW also fit the 70-81 Firebird), but only about six inches on the 67-69 F-body and 68-74 Nova.
That means that a 1-1/4" with a 12" swing has a similar tension as a 1" bar with a 6" swing.
Plus, there are bigger bars if you really want them. I believe there's a 1-1/8" for the first-gen, but one inch is usually the largest you'll need.
I had a set of Herb Adams VSE bars on my 69 Firebird. One inch front and rear, with block mount on the control arm and heimjoint links. I think Adams' bars were actually made by Moroso. (I also had Adams' steel/nylon control arm bushings, rather than those crappy polyurethane.)
Addco also made a one-inch bar for a traditional loop-end for conventional links.
I'm sure there are others, check with Global West.
Glenn Uettwiller
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