Looking that part up, I'm doubtful that is your problem. I haven't seen one of those need replacement for the 15 years I've been on this forum. Be sure you watch that video in my previous post AND read the posts on that thread. You should use the search box in the upper right corner of the Forum and toggle the "threads" option just to the left of the box to google search. You will get loads of associated threads of information. link to part: lock and associated parts

I'm in South East Alabama. If your not far I may be willing to help. Where in AL are you?