Hi all, 
Not sure if this is the correct place to post, but I need a replacement for my common room door knob. 
Apparently it can't be used anymore and when I dismantle it, the inner part of the lock is crooked. 
Went to a nearby shop that sells door knobs and the owner tells me that it's very hard to find a replacement, 
and apparenly I can only use back the same kind of door knob!   
I attached a few pictures to show y'all. 
Anyone knows where to get a replacement or any lobang to get maybe a handyman to fix it? 
 
from inside  
 
from outside 
 
crooked part