This is an American Craftsman 50 series

Hello!

It's hard to say without seeing the original handle and mortise first but I'll try my best!

Take a look at our 82-030 handle set that measures 3-15/16" on installation hole-to-hole center spacing. As for a mortise lock, please see our 82-218. Look over the dimensions for each of these items and see what you think.

Just keep in mind, this is an educated guess and I can't promise that this will work for you.