The rear sight on a used S&W 645 .45 ACP I recently acquired is chipped, so I'm looking for suggestions on a replacement.

All I've found online thus far is a choice between a Pachmayr and an LPA target replacement, both adjustable, in the $60 range. That's about all I'd care to spend.

Anyone with experience on either manufacturer's products?

Also, I tapped out the old sight with a punch and was wondering if there were a special tool for installing the new one... or is it just a "be careful not to mark up the new sight when tapping it in" type of deal?

This is the LPA from Midway, only the target model currently available... I'd prefer either the white circle or white block imprinted variation.