Dear Daniel,
Your pen is most likely a Sheaffer Touchdown Admiral c1950-1952. I don't see a lever on it, so the acid test would be to unscrew the end of the barrel - there is a cap there, and extend the plunger. If it looks like a rod, it's a late 1940s Admiral Vacuum filler, if it looks like a silver tube, it's a Touchdown Admiral.
Touchdown pens use a rubber sac that is compressed using the pneumatic action of depressing the plunger. The sac fills as it recovers from the brief vacuum created.
Either way, you're going to invest at least $35 to get it into working condition.

Sheaffer Touchdown Admiral Black and Burgundy 1950-1952
They were inexpensive quality pens when new, and can be nice writers. Consider the total acquisition cost when buying.
You can learn more about the Sheaffer Touchdown Admiral here:
Sheaffer Thin Model Touchdown Pens 1950-1952FWIW, Sheaffer basically stopped using the Balance name in 1941.
Cheers,
Jim Mamoulides
www.PenHero.com