Just ran across this cool company
Cryopro Cryogenic Tempering Processing Center
Looks like they will cryo treat pretty much anything...
I may need to send them a couple of gun barrels

 

those prices arent bad either. you can do a 4cyl engine block for $200

 

Ohhhh...ive been meaning to have the yokes and transfer case output shaft done....

 

I had all my stuff done. The last stuff to get done with my brand new gearbox. I just wanted to over build the thing. I hate taking stuff apart twice.

 

Hmmm - just found a local place
Byington Steel Treating Service
I'm gonna need to give these folks a call and see if they'll do small jobs

 

Update - I spoke with Byington, he's willing to do small jobs but his cryo rig only goes down to -100 deg. Not really cold enough for some of the stuff I want to do.
He pointed me to Aircraft Engine Overhaul in Palo Alto who can do -300 deg. They are aircraft engine rebuilders and have a lot of cool stuff

I left a message for Victor earlier - please don't call him until I hear back. I don't wanna inundate this guy