Making another Hawken trigger today but did come across a tumbler disc left of from my lock making days and the dimensions are shank diameter is 5/16ths,thickness is .234,diameter 1.235 and the support shaft that goes thru the bridle is .141.It is 1144 "Stressproof",easy to work and hardens in oil.IF you can adapt it to this lock I will sell it to you for the cost of postage.I do no repairs on locks unless it's one I made back in the "day".
Bob Roller