So far i not sure this watch is original product from Omega or...i got few doubts about this watch 1)Omega word and symbol Ω not 3-D 2)Omega production of this model?how come i cant research any information about this watch i hope to get an answer from here,thanks=)
Look up Omega 167.005 in the For Sale corner...that should give you a good indication about how correct this watch is.
It is fake. 167.005 is the model number, as inscribed in the caseback. Google that and you will also get more info.
400 is not a small sum, but at least you didn't pay more. If you are interested in vintage watches, stick around. You will learn a lot.