Is there available a one-piece striker-firing pin the M1903/03A1 actions?

Would a pre-64 Winchester M70 striker-firing pin-cocking piece assembly fit? Or, perhaps, any M-70 assembly?
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The 1898 Krag action has available receiver sights that attach by way of the sight replacing its magazine cut-off assembly. Is a similar sight available for M1903s, or does such a Krag sight fit the M1903's action also?

Not in this century or most of the last one.
No. but the bolt shroud threads are the same.
No.
It would not be hard to make one that threaded into the cocking piece.

a post 64 safety can be fitted to a springfield bolt ... so the lore says .. i have the parts somewhere to ty

As Jeff stated, yes a post 64 M70 sleeve can be fitted. Threads are indexed correctly and will time with an 1903 bolt.

One piece firing pin, contact Ed LaPour to see if he has any or would make one.

J Wisner

Glen chapman used to modify enfield pins if I remember right. I have the drawings somewhere, I'll try to find them.
Don

Numrich used to make a one piece firing pin for the Springfield, but I have been unable to find a listing for one in their on-line catalog.

The Pacific Gun Sight Company made a receiver sight called the S1, as a part of their "No Drill" series, which was attached to the magazine cut-off on the left side of the Springfield receiver. As the name implies, no drilling and tapping was involved, but the sight was locked in position with two opposing set screws. I have never seen on, but a photo of one, which I have been unable to track down, appeared recently on one of the shooting related web sites. It is described and pictured in Nick Stroebel's "Old Gun Sights & Rifle Scopes, Identification & Price Guide."