Are you kidding? The 627-1 is a rare bird! It is the last of the checkered top strap 627s. You will need a checkered rear sight to match the top strap. A 627-0 rear sight might fit if they did not change the front screw location between the -0 and -1. There are some other folks here that can answer that question. There are probably some aftermarket sights available, if you get desperate. I, personally like the S&W rear sight, but I have been using them for a very long time.
The 627-0 has been selling for $1200 up, so I think you got a fine deal. They are great shooting guns!
The 627-2 did away with the checkered top strap and the 5.5 inch barrel.
Like others, the red dot needs to go away, but I would shoot it until I got some irons on it. It is way too tall above the bore for me to handle.

I am envious!! Enjoy that beast!

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Richard Gillespie
FBINA 102