Deer on right appears to be older to me. Larger body in general more developed front end and bigger but and has/is developing that beer gut look.
Id say the one on the left is 3 and the other 4 maybe 5.
Or maybe left is 2 and right is 3-4?
Ive never laid eyes on an Oklahoma deer though.
This almost perfectly matches my thoughts.
But that includes the last sentence as well, so take it for what it's worth.