[Mystic ZR-1]

Check out Lonestar Caliper Co
They're always at Carlisle.
They do sell retail even though the website
doesn't make a big deal out of it.
They have rebuilt with stainless sleeves and you can
get them powder coated too.
Prices quoted at Carlisle don't look too bad?
Never bought from them, so I can't give a 1st hand account...