looking for some opinions if this is just another valve cover replacement or something worse

the individual plugs had it the worst the threads were covered in oil, unfortunately i can say three plugs had oil in the well not a lot two plugs and a good amount of oil on the threads including that 1 plug pictured. there's no oil in the coolant and im sure this explains why my car smells like its burning oil under wot. im not sure if its just oil seeping into the threads and a its another value cover job or worse. this engine does have 140k in miles so i wouldn't put it past it. im going to do a compression test later today.

thoughts suggestions and opinions would be appreciated

http://imageshack.us/a/img818/4724/crt2.jpg

http://imageshack.us/a/img40/1382/3ov.JPG

http://imageshack.us/a/img818/326/yt0z.jpg

 

Are those the original plugs?
140k on those plugs?

 

i have no idea if the original owner ever had the plugs changed before i bought the car, also do to a mistake i made with a plug change when i was younger and still very inexperienced with motors. so its very possible.

i ran a compression as follows
cyl 1- 185 psi
cyl 2 -180 psi
cyl 3 -195 psi
cyl 4 -205 psi
cly 5 -170 psi
cyl 6 -175 psi

my neighbor who does diy articles for car and motorcycles magazines," very Knowledgeable guy" was suggesting for cyl 4 its possible that there is oil in there especially since the worst looking oil cover plug came from there. im curious as to how it got there since the compression inst low for that cyl but higher. which id assume its a good cylinder?