The only Bushnell scopes I trust are the elite series, beyond that I think they are very flimsy. I would upgrade the scope before I went out west.

You'll want a good set of Binos, I prefer 10x50's. I have used the Leupold Wind river series for the last 5 years with no complaints. They are a good bino at a reasonable price, but they do not compare to leica and swarovski.

I never got into the range finder craze. I can judge yardage pretty decent. They main thing with a rifle is to be able to recognize the limit. 300 yds is a long ways. As stated before you can zero your rifle to where the drop isn't an issue out to 300, but that isn't the whole story. I suggest you find a 500 yd range and start praticing. Get the fill for how hard a 300 shot is from field positions. At the same time you fill be learning to judge range. Make mental notes as to how far 300 looks. 300 will be your target yardage. You will want to practice till your confident you can keep all your shots within the vital area.

Shooting sticks can be helpful. I must be honest though I never carry mine. I can usually always find a rest. My rest can be a tree limb, my pack, a rock, etc. Or in a pinch I can wrap my sling around my elbow and form a fairly decent free hand rest. You should go to your local army surplus store and find the field manual on army marksmanship. Read the chapters about slings and battle positions. You will be surprised how accurate you can be if you practice shooting using proper skills.