Can't speak for all Vivitars of that era, but the one I own is a nice lens I use often (105mm 2.8).
The fact is says "Auto" on it probably means it's from the 1970's, maybe early 1980's. I think that was the era the Vivtars were being made by Kiron. "Close Focusing" means it's a Macro lens.
3.8 isn't too bad for a zoom that long. I'd say try it out, see what you get.
I bet it's heavy as a brick (which I love).
What mount is it? If you're lucky it's M42. I know they made it in Nikon mount.