From niche business role - finding a new job?

[Undirection]

My brother works in M&A (business sales) and he's had enough, despite being pretty successful. However, this sector is quite niche and he doesn’t know how to, or more precisely where to, look for a new job outside M&A. I guess he has transferrable skills but I have no idea either. He’s probably on £80k-ish. He worked in a niche financial area in the past but its 10 years since he was there and he wonders if he could go or would even want to go back to that.

Just putting his CV on a generic website seems a bit non-specific. Are there ones that he may be better using (higher paid jobs?) or does he find an actual recruiter, i.e. a person more than a faceless company.

Any help much appreciated (by him).