The door to the coat closet off the living room jammed and would not open. Taking the entire door off, and door knob, I eventually got it open, to find that the slide for the bolt was broken and the shaft going thru it was twisted. These were the original hardware pieces from when the house was built (Gainsbourgh), so it was 30 years old.
Rather than try to find the correct replacement pieces, we replaced the entire mechanism with a more contemporary lever handle, similar to what we have on the kitchen/garage entry door. This is a Kwikset Tustin Satin Nickel Hall & Closet (720 TNL 15) Signature Series, $31.25 from Home Depot.
This is continuing the switch from the polished brass to Linda's preferred Satin Nickel finish, and also switching from crystal door knobs to levers.