It looks fine, whether or not the o-ring is rubber or hard plastic? It's a over ten year old car and I never checked when we first got it whether or not the o-ring is made out of. If you don't see no leak, which I do not see any oil residue outside the valve cover of your picture, then it is working as intended. You should be good to go. IF you are suspecting oil is disappearing, the 2AZ-FE is a known oil burner and the real only fix for it is essentially a engine rebuild by replacing the pistons & rings with updated parts.
All of that is hard plastic. Is that what it should be?
Sent from my iPhone using Tapatalk
You should be fine. If you want to change it you can but since the oil cap is screwed in properly it and the o-ring you currently have will do its job. Mine I somehow over-tightened and it either damaged the o-ring or the plastic itself causing a relatively light oil leak. If you don't see no oil then you are good.View attachment 295982
I wasn't worried so much about oil consumption as much as I saw there was one when looking at this diagram. (I just replaced the plugs, PCV valve, and Valve gasket cover.) Looks like part 12108A. I didn't recall the gasket when I changed the oil and wondered if it was necessary.