Hi Dave and welcome!
Ruger walnuts in the barrel banded carbine R model were first SE Overton's from the inception (1964) until 1971 Ruger then began manufacturing the walnuts themselves from 1971 until they became a cost issue in 1984. First Birch, then for a short time maple and back to birch was the sequence of materials used from 1984 to the present.
The metal buttplate which is specifically aluminum was present from 1964 until the Liberty Model guns of 1976 at which time they were replaced by GE's Celcon. The C-63 is a part number. The early Celcon buttplates were installed after the stock was finished however they were inconsistent on fit. Much later Ruger installed the Celcon plate before the final standing on the stock which provided a very consistent fit.
The DSP stock with it's checkering and sling studs continues to be made of walnut today.
The real beauties were the original SE Overtons of black walnut.
It's a hobby of mine to rescue these pieces of Americana for restoration.
Here's a few of mine:
1966
1968
Rescued (before)
After
Hope this helps!
SD
