I just got my master cylinder back from Brake & Equipment Warehouse in Minnesota.

They did a super-nice job.

They baked and bead-blasted it followed by a bore and hone.

They pressed in a new 304 stainless steel sleeve and drilled the ports.

They installed a Raybestos MK662 rebuild kit and a new cover gasket.

They said that DOT 3 or 5 brake fluid can be used in it.

It was a one-week turnaround.

Brad's the man

http://brakeandequipment.com/

They have a cool video under their "machine shop" tab too.