There are those who have to feel that they "stole" a purchase to enjoy it; others who just think "Well, I paid what it was worth TO ME." I've always been one of the latter. Under four for a solid 20ga with a little history seems fair to me; betcha you get more than that amount of enjoyment out of it!
The SN is a mystery on a Stevens gun of that age. It's a Ranger so I assume it was sold by Sears Roebuck; could they have specified serial numbers appear on the guns? Seems unlikely they'd have gone to the trouble.
