The only .44-40 I've owned was a Merwin-Hulbert.
A very good gun in its day.
I'm not certain which model I had. It looked like a 4th model Frontier but did not have the folding hammer shown in pictures. It had the top strap, nickel finish, and ribbed 3-1/2 inch barrel. It was in pretty far shape, nickel a little chipped in places, but lockup was solid.
Tom