Direct replacement. Just like the stock ones but higher quality. protegegarage.com sells them, as does nsnmotorsports.com.
I love the Tokico HPs just because they're really nice, but with my Goldline lowering springs the ride is so painfully harsh even with the Tokicos. I don't know how much I believe that the stock ones only last 60k miles, because mine weren't feeling too worn or blown at 63k miles, 30k of which were on the Goldline springs.
I think the Tokicos have like a lifetime warranty or something too.
Does anyone know if the steel thing with the rubber that clamps the spring onto the strut needs to get replaced? I know my roommate replaced his when he got new struts but his Volvo also had 210k miles at the time haha.