That's correct, they no longer sell them. Whatever oil filter you use, be sure that it measures no more than 2?" in length. If it is longer than that, it will be punctured by the centerstand.I suspect they don't sell them anymore.
I order online from South South Honda (hondabike.com) and select to pick up parts at the dealer instead of ship the parts to my house. Their prices are cheaper than the 4 links you gave for an oil and air filter, and pick up is free. They have a dealer in Tacoma & Olympia. Phone-in or walk-in orders may not be the same good deal as online orders....not sure though. Order several filters and make it worth the ride to the slumming south sound.So where have you found the normal consumables at, like oil and air filters at a reasonable price?