1984 4-Speed - WIW?

I found this 4-speed in my stash. I want to say it is a 1984 4-speed overdrive. It goes through the gears fine, but has been sitting around for years so should be gone through. Was wondering what it might be worth. Sorry for the sideway pics, no idea why Moparts is doing this to me??? Thanks.

The input shaft doesn't look right. The splines look different than a 23 spline shaft. Maybe it's my eyes.

Weren't there some later GM trucks that used 833's ?

Yes. Around 1980. Here is an article. GM-833

Interesting article, learn something new everyday. Thanks. Looks like that is what I have. The 80-85 GM version of an A-833.