Found in my door (72)...What are these?

[MXC_Rider]

Hey guys, been a member for a while now and finally picked up a '72 blazer a few weeks ago. Im starting to do some of the simple things such as rewiring radio, fixing headlight wiring, trans rear seal etc.
Right now i'm replacing the door locks and when i pulled everything apart i found these two brackets at the bottom of the door just lying there. One looks like it may be original with surface rust, and the other looks like a replacement???
Any idea what these are?

THANKS!

M