Based on my knowledge, a qualified manager with about 6 years working experience is about 15k. Since you mention your manager is equals AM, I think it's about there.. With a promotion you'll be able to hit over 15k. Of course, that depends on which company you're joining as well. Some companies (2 of the big 3) can seriously pay very good package from what I heard.

He's a qualified actuary and have moved up the ranks pretty well. That's about the market average salary I think..

Local or overseas graduate doesn't make much difference in general.
Anyway, I am not sure if I can fully agree that actuarial pay is really super high..
Comparing against non actuarial, maybe it's true in the earlier stages of career. However, in later stages, I would say while it's slightly higher, it's not that much higher..
Say, a senior manager in other department could be earning about 15-18k while an actuarial senior manager would perhaps earn about 10%-20% more. the gap reduces further as you go up the ranks.