Avoiding those brands purely because they are quite common (not dissing those brands I wear a Seiko myself).

Was thinking of brands like Oris, Longines, Hamilton etc. Can these be had at that budget? It's his birthday so thought of giving him a decent watch but at the same time he doesn't take care (judging from his existing watch) or wear it often.

yea maybe hamilton. Oris and Longines are expensive, even for the second hand unit are close to 10k cheapest.
the problem here is there's a vacuum area between 5k to 10k for decent watch. that is the area which the top teir japanese watch are comfortable-ly sitting / smaller swiss brand like tissot. Another brand like Bell & Ross is good but its around at 10k mark and its more to youngster. 

I wont be recommending fashion brand like cK, boss, fossil, bonia etc etc as that doesn't looks well on mature men. If 20-30, those brand will work.

If you are looking after brands like Tag, Oris, Longines, Omega, Rado, you might want to invest more even for a second hand unit.

If you are in budget, look for Seiko premier/orient star mechanical, the brands are common but these watches are not. They look elegant also.