I wonder what a gunsmith would charge to do a mill/insert job on that. It might be worth it. First, check that frame over real close for cracks. There was a polymer buffer on the slide spring assembly, and it has probably worn out and disintegrated some time ago. The gun will shoot without it, but it's real hard on the frame. Those buffers are still available, and if you opt to keep the gun, you might want to find some.
I have a PD, and I love it. It's a sweet shooter.
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