Hick,
Barbie is Jim's daughter, if that makes a difference. His wife is Karen.
The Small Siler will not fit the mortice without a lot of wood shimming, and the sear bar will not fit the triggers, without a lot of work.
The old CVA flinters were pretty poor sparkers anyway, and I can not see spending $100 for a new Siler lock on a $100 gun.
Regards,
Terry