I see one outfit that sells springs and grips for SAR 45's, but nobody that has
parts that might be used to customize a K2-45 for fine touch target shooting.
That said, I know NOTHING about gunsmithing, so go easy on me if this is a
stupid question.
I assumme you are asking about the Sarsilmaz SAR K2 45. It's a Turkish-made clone of the CZ-75B. You might contact Cajun Gun Works and ask if they have any recommendations.