These are the legendary Jcurt455 Autococker half block kits. What's included: delrin high flow bolt (with o-ring installed to retain the pin), delrin sled (standard 10-32 threaded), and aluminum pin.
What you need for install: half blocked cocker body, modded hammer, pump arm.
I have these in hand and they'll ship a couple of days after payment.
I do not modify bodies or pump arms, but if you post in the Airsmiths section you should easily be able to find someone to do the work. Price: $35 shipped per kit
Note: Jcurt455 has stated the intended purpose of selling these kits is to gain capital for completing outstanding projects. I will not act as a liason between you and Jcurt455 for any projects you have pending. Do not PM me for anything related to those projects or his contact info.