You provided way too much information. No gun manufacturer wants to hear you customize it, and it also relieves them of any manufacturer warranty. I have quite a few Savage actions builds and had no problem dealing with Savage. The phone call was long, but they have always come through, and most of the small parts were free. The ship to gunsmith only is new to me.I decided to contact Savage and I got utterly zero help. Since the rifle has a custom barrel, they won't help me, despite the fact that the bolt/receiver/etc is entirely OEM. On top of that, they only sell bolt/trigger parts to a licensed gunsmith.
Try https://www.gunshack.com/savage-parts. Order from Numrich what you think is the correct part. What do you have to lose, esp. from an action you have no idea what the previous owner did. You cannot base the parts you currently have on what the parts breakdown shows. Good luck!