The late production rollmark above the trigger, 3 line instead of two, would cause me to lend credence to the replacement frame.

That 469 looks like an early/original top end on a late production 6904 frame. That would be my bet.

An officer I knew at another agency had an original 669 that he shot the snot out of. Unlimited ammo supply and a job at the police range, combined with poor maintenance (oil instead of grease, old recoil springs with hot duty ammo) caused his frame to crack above the slide stop.

The S&W LE rep took the gun and told him he would see what he could do. He came back a few weeks later with the original top end mounted on a 6906 frame. It looked very much like your 469 does. Hope this guess helps! Regards 18DAI

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