"...made it's way into a laminate stock..." Lots of 'em used on pre-war "export" K98's. All the literally mint condition(friggin' things were still in the grease. Came with the matching bayonet too.) Portuguese contract(1938 or so) rifles we had in the shop, long ago, had laminated stocks.
"...welded on another sling attachment..." Highly unlikely to be Bubba. Same colours.
That's a bolt not a stock disk like those seen on Lee-Enfields.
Rummage around here.
http://mauser98k.internetdsl.pl/gbkomen.html