Be sure what the seller meens by early. Often people say they have an early rifle and it turns out to be 1980s or newer.
Some advantages to true early rifles non-prefix up through 130-05000 or so will have a Douglas Match Grade Barrel, 3 screw, adjustable trigger, red pad with smooth edges and no warning on the barrel.
I personally only consider guns prior to late 1976 with one of the two earliest checkering patterns as "early". After that there really aren't many changes that show up. Might consider all red pads or maybe pre warming but that's into the 90s for Red pads and I personally don't consider a 90s #1 early.
A gentleman had one on Guns America a few nights ago. It was an early gun and was in 243 with a heavy barrel. Well, the 243 "V" is a very rare gun in #1s.
Several of us inquired. Turns out it was a 243 "B" standard rifle with a serial number in the 133- range, made after 2000. The seller wasn't even aware that Ruger #1s came in the "V" profile with scope blocks.
Be sure and find out what your seller means by EARLY.
the best
Ross