compression release

Hi all , newbie here. Hope I am posting this in the right spot.
I Googled this and it led me here. How much and where do I get it ?

www.accessnorton.com/NortonCommando/compression-relief-valves-to-allow-easier-kicking.22401/page-2

Kibblewhite sells them for $50 / pair. I installed them on a 750 and it reduced the kicking force by maybe 50%.
The location is just outboard of the spark plugs. I will install them into an 850 head soon and see what happens.
An estart from CNW is at least $4000 with labor.

Big Husky men do not need a compression release, You guys need dog-sleds.