The Kawi OEM's are always available and in stock at my dealer and I've
never had a problem removing one. Of course there was that awesome first one put on by the
"HULK" at the factory...that's another story, but no probs since!
A cheap $5 end-cap wrench that's available at any auto parts store works great and is the alternative to having a "nut" welded to the filter. It's what I used on that first one from the factory. They come in various sizes and you just have to make sure you get the one that fits the end of your particular filter. My 2 cents, YMMV.