Bolt face change

[Cat 64]

I currently have a rifle in a 308 sporting a Savage Target Action (RBLP) single shot with a .473 bolt face. I want to use this as switch barrel rifle and I am contemplating going the 7 mm SAUM route. Can someone please tell me what bolt face do I need (I believe is a .540) and what process/other parts are involved in changing this. Also where is the best place to find these components. Thank you.

[drybean]

Just The Mag Bolt head