OK, I'll try to answer all those...
Will5A1: All ammunition was ball/FMJ, hollow points etc were not even considered, too many ex-military in senior ranks with memories of the Geneva convention.
Pension? most Brits (with some Aussies, Kiwis, South Africans and a couple of Canadians) went out on 3 year contract terms, we were young and pensions weren't really of interest. I think it was about 25 years for a pension. Also I should point out that the expatriates went with the rank of inspector, equivalent to military lieutenant. There were about 400 expats as officers in a force which totaled somewhere around 25,000. I think there is a group who have annual dinners and such here but I never bothered.
I have a book called "Asia's Finest" by a chap called Kevin Sinclair but it's long out of print. I think there's a more recent edition out by the same chap called "Asia's Finest Marches On" or something like that. Not sure if it's any good.
Cosmo: I haven't a clue what's happened with their sidearms since the changeover. Incidentally, when I was there in '75 there was also the old Webley 38 short (MkIV???) which was carried by the Auxilliary police (part timers). They were phased out when the new S&Ws came online.
Bart Noir: I'm no gun expert in any way shape or form (obvious, eh?
). Whatever it was I remember it as a 50 calibre heavy machine gun on a mount and with an armour plated shield... a bit like the WWII U boats. I thought I remembered it as a Bren but can't find any references. It may possibly have been a Browning ? but that doesn't sound right, I'm certain it wasn't a Boys...Whatever it was I think the crews would never dare fire it as it was probably more dangerous to them than to whoever they were firing at, it being so old and constantly exposed to sea air. If they ever had to "put a shot across someones bows" they'd have used the AR15. I didn't do any time with the Marine Police so I only ever saw them with their canvas covers on. I checked my book but it doesn't have any photos of police launches with the armament visible. Sorry about that.