>>3206654A simple monopod setup with a tripod or walking staff is the most you'd need unless it is rather overcast and dark. You don't even need to attach it, just use it as a 3rd leg and touch the camera to it. 300mm is great. The wider your front lens the more light it will bring in and the faster you can do exposures.
>>3206696I haven't seen shutter speeds faster than 1/200 without flash in like....ever. This one was 1/50 I think with my 300mm kit lens. Everything is so overcast these days it sucks a lot.