I am considering a K-22 SN#K70135...about 98% condition, it is a beautiful revolver...one caveat..the grips are some aftermarket plastic target grips. Sort of mottled white/ivory in color..but have the checkered pattern with diamond in the center where the screw is located. The revolver is 5 screw with pinned barrel..possibly recessed. Is this revolver worth $540 with the additional cost of replacement grips? Anyone familiar with the aforementioned plastic target grips? I am thinking early 50's production but it would be nice to pin it down with some help...and I do appreciate any info and feedback.