I bought the power steering cooler kit from the other thread from him, was a good sale. Probably with a garage full of stuff, that underdrive pulley just never sold the first time and then sat for a long time. Then this time it got posted for sale and got sold outside the forum and got a little weird... I'm glad to see TRS has added the holes now which makes it easier to counterhold the pulley.
I've got the RSS pulley installed, felt like a nice little boost, but what a hassle sawing off that boss with a small hacksaw... I got mine for about that same price second hand.
EBS (a well respected name in Porsche) looks like they ave a kit now with an intro price that is close to the price from this thread:
https://www.ebay.com/itm/Porsche-Boxster-Cayman-996-Performance-Underdrive-Pulley-Kit/112529147463?hash=item1a33428647:g:vfoAAOSwTtpZlc4 V&vxp=mtr
Edit: Looks like there is a fib on that listing though, says "no modifications required", unless this pulley is nearly as big as stock it isn't going to clear that boss...