To give you an exact identification on this watch is next to impossible.

At the time this watch was produced, around the mid-1970's, Omega was making hundreds of different models every year. Some were very limited production runs and of other models they made thousands.

The "8374" is the case reference number. Generally, these can be looked up online at the Omega Vintage Database:

http://www.omegawatches.com/planet-omega/heritage/vintage-watches-database/

For this watch, there is no information on the database. That happens a lot with these 1970's Omegas. They couldn't keep up with all the models either. The "1011" would look to be the caliber of the movement. That is interesting, as the cal. 1011 is a chronometer rated movement, mostly used for Constellations and Seamasters, but there is no indication of that on the dial.

It is 18K gold, and the other markings are either Swiss hallmarks or maker's marks.

So this is a nice original 18K gold Omega automatic watch. Right back where we started.
gatorcpa

 

I hope you don't pay a lot more than the melt value of the case. These are not considered particularly collectible watches.

Good luck,
gatorcpa