i got an idea to get 24 pin atx power cable extender so that its not so tight and give it a better look.

what i need:
-the 24 pin atx power male conector.(black)
-the aluminum things.... that lock in the cable in to the connecor and dos it job.... what are thos called?

what i have:
-sodering gun,
-sleeving,
-cable,
-tools,

where can i get these?