a couple companies make decent SAR vests but (with one exception) none in bright colors that are worth a damn. I have spent years looking without success. I did find a few manufacturers willing to make current or custom products in any color of cordura, however you pay the price and wait times can be from extreme to ridiculous. I do have a custom manufactuer that is currently making a Bail-out bag for me, that I plan on having him build me a custom rig for SAR work... until that happy day I am still tinkering with my setup.
EMS vests like JIM posted have multiple issues that make them unsuitable for Wilderness SAR or even USAR. These vests (as another noted) are far from "Load Bearing" and most are uncomfortable after a short period of time. These vest may be good in some situations, carrying limited amounts of gear from an ambulance to a wrecked vehicle in a ditch for example they just don't work for SAR.
Special Force's Gear makes a couple SAR/Survival vests that they offer in Blaze Orange (and the cheaper one in Tan). I have used one of these in the past but found that it failed to fit my carrying needs in the long run. While this vest is IDEAL for mounted SAR work (ATV and Horse) it is uncomfortable with a pack and the attached expandable pack is not quite big enough for longer missions with more then personal survival equipment.
I have recently started using a
TrueNorth Aerovest which is much better suited for SAR and is comfortable enough for use with pack. The vest carries enough for personal survival needs as well as some basic tools and medical gear. It is still black, but has some reflective on it. It is a load bearing vest and can be equipped with a belt and additional pouches. This vest is better suited for USAR (which it was designed for) and shorter simpler missions (less then 24 hours). In fact, setup right with a belt and additional pouches/packs this vest is more versatile then the SAR vests mentioned above (although the more expensive SAR vest is built by SoTech and it is bombproof).
Also a high quality vest, designed again primarily for USAR is
Wolfpack Gear USAR Load Bearing Harness. Again, it is comfortable and can be expanded with a belt and pouches. But again, is only offered in Black.
In the end, for longer missions I choose to simply use a larger radio chest rig that I can carry some basic survival stuff and admin tools in and keep the rest of my kit in pockets and the lion's share in a good pack like the
Conterra Longbow Ranger (link chosen for it's pictures, after the exceptional service I have received from
Conterra I purchase all my stuff direct).