Nikon fm light seal repair and cleaning?

I recently bought a Nikon fm 35mm camera, and the light seals are basicaly gone, and the mirror is extremly dirty.
Where can I get this fixed and any idea how much it will cost

Check your local telephone directory for Camera Repairers and negotiate a price with them.

It will probably be quite expensive to get the camera serviced (although possibly worth it).It's not hard to do it yourself, though. Light seals are easy to change. Search on eBay for "Nikon FM light seal" and there are premade kits of the seals with instructions for very little money. You need to use a knife to scrape out the old black stuff and then simply stick the new seals in place.

Cleaning the mirror can be tricky because it is extremely delicate. Use rubbing alcohol and a lens tissue. Don't rub the lens tissue on the mirror with the pressure of the finger. You only need as much pressure as the weight of the tissue being dragged over the mirror without pressing. The good news is that the mirror does not affect the image quality of the pictures - only what you see in the viewfinder.

Working on your own cameras is a fun way of getting to know them better. Until 2 years ago I'd never worked on a camera before and now I've changed light seals, cleaned mirrors and lenses and dismantled the guts to lubricate the gears and threads. It just takes patience.