Neither, if you can find one, (needle in haystack) you need one with the bakelite dogs head insert (7/8")in the forend wood.
The roller release was on ejector guns or after 1919 on grades Ideal and above without ejectors. The Field grade was pull-off forend. The push button release (Curtis)was used on all non ejector guns from 1913-1919.
There is a chance the other forend wood and metal might fit if it is a Regular frame (R),or have to be fitted as even the lowest grades had some hand-fiting done at the factory. The "J" spring is where you might have a problem with the fit. The best way to tell is to take the wood from the metal and just try the metal to see if it fits.
The 0 grade became Ideal Grade after 1913.
Last edited by JDW; 07/06/09 07:19 AM.