That's a beautiful 6105. I'd definitely be picky with where you send it, I personally wouldn't send it to Seiko/Mahwah, NJ. I'd look for a smaller, more specialized place that could do a "sympathetic restoration". You don't want to lose any of the character/patina your dad put on it, just clean the case (I'd suggest avoiding any polishing on the metal), and a full mechanical service.
If it was my watch and I had my choice, I'd probably want to send it to Spencer Klein at Klein Vintage, https://www.kleinvintagewatchrepair.com/. He hasn't been accepting new work for a while now due to his huge backlog, but it might be worth e-mailing him to see if he might be starting back up soon. He has many great videos on Youtube, very transparent with his customers. Duncan is another option that is currently not accepting new work due to his backlog as well, https://thewatchbloke.co.uk/ . I've never used them, but I've heard good things about VTA (Australia), http://www.vintagetimeaustralia.com/
Wherever you take it, it won't likely be a cheap service, but it'd be worth it.
If it was my watch and I had my choice, I'd probably want to send it to Spencer Klein at Klein Vintage, https://www.kleinvintagewatchrepair.com/. He hasn't been accepting new work for a while now due to his huge backlog, but it might be worth e-mailing him to see if he might be starting back up soon. He has many great videos on Youtube, very transparent with his customers. Duncan is another option that is currently not accepting new work due to his backlog as well, https://thewatchbloke.co.uk/ . I've never used them, but I've heard good things about VTA (Australia), http://www.vintagetimeaustralia.com/
Wherever you take it, it won't likely be a cheap service, but it'd be worth it.
