Restoring an old wood window

I am in the process of restoring an old (~80 years) wooden window (from Andersen). This window has a double pane with the inside pane metal and removable (like an inside storm window). Between the outer pane and inside pane there are two wholes in the window frame that lead outside. I suspect that these holes are needed for the winter time to reduce the condensation. These holes have metal and plastic plugs (on the picture below I show a metal one). Some of these windows miss these plugs and I would like to buy them. I, however, have no idea what they are called and whether it is actually possible to find a replacement. So, can anyone identify these plugs and, ideally, point me in a direction where a replacement can be purchased. Thank you.

 

The only source for that part would be from Andersen, and I doubt it's available. Those windows are from the 1960s.

 

Not sure if this is an exact replacement , or if it's still available.

https://parts.andersenwindows.com/detail_0533008__w_wcasement_sash.html

 

Wow! This is exactly what I want. Thank you so much.