[MattNH]

Hi and welcome. The rear sights on the 99M1 and 989M2 are pretty hard to come by. Most people removed them for a scope and once separated, rarely come back together. The best bet will be ebay and be prepared to pay.

I was lucky enough to find mine with the rear sight. And we like pictures here so lets see the 99M1

 

[MattNH]

If I ever find a 99M1 or a 989M2 without the rear sight I will definitely mount tech sights on it. Typically on these rifles the front sight was a band that has a set screw so I would need to drill and tap for the tech sight front, but so worth it

Link to Tech Sights for Marlin

 

[MattNH]

I'll add a pic

 

[MattNH]

Nice work!