About two years ago, I sent off a circa-2007 Omega Seamaster automatic for repair and a general overhaul to a west coast company which performs a lot of Omega repairs. The cost was $600, and they did a great job. I could justify the expense, as it preserved the value of a watch worth 4 -5 times that amount in good repair. While some parts were replaced, most were just examined and cleaned and lubricated as necessary, so most of the internal parts of my watch are still from 2007.

I expect that any parts your watch may need are more reasonably priced than Omega parts, but the labor cost will not be much less than it was for me. You're probably at the point that a watch replacement may make more sense, although the price of a good watch, like everything else, has gone through the roof over the past few years. My used Omega is worth about twice the price that it was when new. While this reflects, in part, the collectability of the watch, it also reflects that a new Seamaster costs 5 - 6 times as much as it did back in 2007. I'm guessing that a new Hamilton would retail $900 - $1,500.

BTW, don't shy away from a watch with a quartz movement. A good quartz movement will last a very long time with little, if any maintenance. I have four Omega Seamasters, with maybe 5 years difference in age between the oldest and newest. Three are quartz, which have needed nothing more than a battery change every few years, and the fourth is discussed above, which just ate six pictures of Benjamin Franklin without so much as a burp...