Well, i haven't seen that exact model before. I'm thinking is from the 20 chassis family. Those are the ones with two chassis. One for the power supply and audio amp, the other everything else.
Possibly it could be the older 30 chassis family as it has a rounded rectangular mask rather than the "double D" shown in the Sams.
Here the Sams for the 20A/B -
http://www.earlytelevision.org/pdf/A...A1_Sams_77.pdf