It could be original and valuable, but you should take into consideration the history of the watch - for as long as you have viable records anyways. If you can get the serial number off of it then here are a couple of links to Omega SN production dating tables: http://www.chronomaddox.com/omega_serial_numbers.html
Or check: http://thewatchguy.homestead.com/pages/OMEGASERIAL.html
or a little ways down this page is yet another SN/age for Omega : http://www.clockmaker.com.au/rolex_serial_numbers.html
Even if your serial number does happen to match up, that doesn't necessarily mean anything as stamping or engraving a number into the back of a watch can be done by anyone.
I will say that there are tons of Chinese fakes floating around that look very similar to the one you are posting about. I am not saying that yours is one of these, but the possibility is very high. Most of the time the Chinese knock offs are simply standard works with the Omega label stamped onto it. Any experienced watch historian would be able to identify this with a very quick glance. Again I am not saying that yours is one of these. I would be cautious on the amount of money spent on getting it authenticated.
One thing to check is the date. If it says made in 1882 then that would be very suspicious as Omega didn't officially open until 1885. Another thing is to look at the word Switzerland. If it says Swit zerland then I would be very cautious. An official Omega dealer should be able to give you the low down on it. If it happens to be an authentic Omega watch, it could be worth well into the 20K range or more. If not, 25 bucks.
Best of luck.
Hope that helps.