Card Game Graphics

I have engineered a very simple new card game, but am looking to make my self-made graphics more professional. I'd like them in a 2D style that is approachable, fun, but not childish.

I wouldn't need all the cards to be constructed individually, I really just need 6 monochromatic card fronts featuring different animals, and possibly assistance with a graphic for the outside of the box (which would likely be just a repurposing of one of the card fronts).

I'm looking for the fee to cover ownership of the art, as I do not want to have to worry about ongoing loyalties if the game ever ended up being widely produced.

Attached is one of the card fronts I already made for the play testing stage of the game so you can see the basic idea I'm going for.

I would like to see previous work examples, preferably featuring animals.