Thanks to all for your thoughts on this

Huvis-
The standing breech on this action measures somewhwere in the 2-7/8" range, I'll have it out of the clink some time this week to measure it again for sure.
I'll post the width and firing in center to center here in the thread.

Sinner-
I've heard strong words of recommendation for Ken Owen elsewhere. I may well drop him a line some time soon.
Feel free to PM me his contact info.
I'll likely run a contact/inquiry campaign of possible builders in the next month or so.

--Tinker