High-resolution scans attached.
The 321's knobs are brown, the color of a Hershey bar. Ignore the gold-plating in the scans. The 325, like you pictured in your last post, has gold-plated knobs.
As rp2813 hinted at, there were 2 tuners, one of which had the channels evenly spaced around 360-degrees, the other had them spaced about 200 degrees with a large gap between channel 2 and 13. You can tell which one your is by whether or not you can spin the channel selector forever, or if you can only turn it half a turn in either direction and it stops. Both types of knob are shown.
If your knobs are missing, then probably so is the brass badge (?). Here's a picture of that:
http://www.audiokarma.org/forums/att...4&d=1163440364