Hi Frank, the US photo company TAMRAC make what you are after. I paid around $US100 for mine if I remember correctly. The Tamrac has model number 53 on it.
Another alternative is a fly fishermans vest, which like a photo vest has a multitude of pockets - inside and out.
I have successfully used both for your stated purpose. The Tamrac is made for American customers who are larger than I, and is designed to "breathe" in hot weather, whereas the fly fishermans vest is quilted and is preferred in cold weather.
Both, as noted, have pockets both inside and outside the vest. Many are zippered (Tamrac), Velcroed (both), or have locking buttons (fisherman's vest). Both have external eyelets for hanging small stuff, e.g. fishing stuff such as flys and pliers, your photo GPS (if you use one), or filter or card pouches etc
Good luck with your trip.
