the feedneck orings seem to be alot bigger than any found on the bolt/bolt stop.
What lube do you plan to use? Anything oil based lube such as Gun Oil and Dow 55 will simply swell your orings, and inhibit performance of the bolt. It causes more friction. I dont know of any oring eating, or else it would of killed bolt orings on my spyder long ago, and bob long wouldnt suggest it as lube for the timmy.
Stuff like Dow 33, or anything dow 33 and non oil based are ok.