Not sure what model I have?

[TnShooter83]

Smith & Wesson - Behind the swing it reads "94 18 4"
It is chambered in .38 Spl

Any ideas on its age and Value?

There is no rust on it, it is just cake generously with oil.

 

[Bullet Bob]

Well, the half-moon front sight means 1951 or earlier. The large knob on the end of the ejctor rod probably means pre-WWII. If you'll give us the numbers (and any letters) on the bottom of the butt, we can narrow it down pretty well.