Bout 10,000 threads on this on cf. I know glacier sells a few different kits as does Vulcan. Not to hard to make yourself if you've got the filter heads and some scrap steel and time. Don't forget hoses and fittings.
In doing this, do you get rid of the stock filter housing? I never liked the kits where you add a filter after the stock housing and bolt on the apps bracket. It just clutters the engine bay up.