Hi Ed
If you need the master rebuilt try
www.johnstuartpowerbrake.com/
Located in Stoney Creek
They have a very high reputation with car collectors, military vehicle collection, etc.
Once the master is resleeved in SS they are good for a life time. He will also resleeve wheel cylinders..... definitely more expensive than new ones but the SS job will last a life time.
Good luck
Bob C