Ok, it's a No4Mk1 but marked No4Mk1*. It's British made and the Brits never made the Mk1*. Savage and LONGBRANCH made the Mk1*. The difference is the bolthead release. The Mk1 has the catch in front of the charger bridge and the Mk1* has a cutout in the bolthead guide rail and no catch. Pretty exciting stuff, guess not.
I didn't realize it was such a common variation. I'll probably part it out to sell on ebay. I'm pretty sure I'd get more selling parts than selling the whole rifle. It's a refurb so no loss of an original rifle. Not sure what to do with the receiver though.