Bolt on SC 1903a3

Hello All,just picked up a SC 1903a3,5/43,ser # 3,975,xxx. The stock is correct.This is my 2nd one as a fool I sold my other one a few years ago.My bolt is the question.Its blued.It has a very small X right in the crease where the flat top of the bolt meets the upper part.The X almost looks like an electro-pencil.Also on the bottom of bolt there is a number 8 with a proof punch next to it.This bolt has the tapered or scalloped lug.There are no other markings that I can see.Would this be a SC bolt ?

Sounds like one to me - pictures?

Sounds like one. The "X" is often poorly struck, although I don't think I've seen one that reminded me of an electro-pencil.