You need nine pin and a octal pin saver. It is best to email them as the first set I got the pins were too small. They had them listed as ones that would work. They took them back with no issues. I double stacked the 9 pin sockets for height, so I had 8 of the 9 pin savers.
Rectifiers I liked: Mullard GZ37, USAF 596, Philips 5R4GYS....