I'll be the first one to prove himself lacking in both knowledge and good sense. I think it's a Springfield NRA-type Sporter that has been restocked by a very good stockmaker, but I do not know who. It is probably one of the double heat treated actions. The Lyman 48 has a long slide. Since there is no telescope and the bolt handle has not been altered, the rifle probably dates from the 1920s. I would take out the bolt, check the bore under a good light and mumble something about "low number action, and not set up for a scope" and offer the chap $575. If he asked for more, I would go up to $650 and not feel as if I were too much of a gambler. If the bargaining went beyond $800, the owner could continue to own it.