Gotta go with Motomataya on this one,. You'd be better off the changing filter without the oil at this point! But don't. The filter is probably full of crap, as when an engine is breaking in, they're scraping a lot of excess metal off. There's more junk in the filter than the oil.
I would venture to say you're not going to find any filters close to this one at an auto parts store. You could probably live without changing the Orings, they should survive a couple of changes without any problem. There are really only three in there, one for the cover, and one on each end of the filter. My mechanic didn't change the inner one. The way it's in there, I didn't see any problem with that. The early oil changes are the important ones, after the second change, they don't need to be nearly as often. I have my opinions about the frequency they have in the manual, but I'm not going to start an online battle here. Leave it to say, I have been a motorcycle (BSA, Triumph, Norton, etal) and aircraft mechanic (A&P/IA) for nearly 50 years and have a lot of experience with air cooled engines. If your so inclined you can take the old Orings down to an industrial or aircraft supply house and match them up, but I doubt you can save much,
but, it would be more convenient than having to mail order the stuff.
The bottom line is that oil changes are the number one priority in these engines for keeping them living a long life. Pain in the butt that it is, don't shirk this one!
Bare