This is a standard steel floor plate from a Winchester Model 70 rifle. It has clearly been refinished, though not in the pre64win shop.
Bluing - Refinished - 95%. The finish on this floor plate is a very smooth glossy blue/black color. It doesn't particularly resemble factory bluing. There are some scratches and freckling visible beneath the finish.
Metal - The metal is in very good condition, with some scratches and freckling beneath the finish.
We use the NRA Modern Gun Condition Standards Grading System for grading part conditions. You can read about it HERE