Small leak from shower drain - Proflo?

[Taki]

Hello,

Recently a very small leak has developed from a prefab shower drain - a few drop to the ceiling below every time shower is used. The shower is about 20 years old, no movement when stepping on. I'm attaching a couple of photos below. It looks like it is a ProFlo drain (https://www.ferguson.com/product/pr...-stainless-steel-strainer-pf140nc/284531.html).

I am assuming a gasket failed - not sure which one, since there are appears to be two gaskets. My question is, is it possible to remove the brass part from top (the manual says there is a special adapter) and replace the gasket(s)?

Thanks!

 

[Taki]

Update: i sprayed some penetrant and managed to remove the top tabbed nut, exposing the gasket underneath. The gasket was clearly dried up and shrunken. I pried the gasket out, and now I hope that I can find a new gasket, install it, and solve the problem.

Can anyone tell me if these gasket are model/manufacturer specific, or i can just find a generic replacement? Also, any tips for installing these gaskets? Use soap to help it slide in? maybe add some silicone underneath?