The reason the other site is asking about long or short action is because there is a newer caliber 270 wsm (winchester short magnum) that is a short action magnum version of the classic 270 caliber that you have (circa 1984).
You are correct. You get what you pay for. You have already heard from "leupold" fans, bushnell, nikon, etc. All of those brands offer quality scopes. However, I would NOT reccommend the leupold rifleman. I have one and am not happy with it. The scope adjustment screws don't have a positive "click" for each incremental adjustment. We put a Nikon ($150) range on my son's 270 and I am happy with that one.
I would also caution you to be careful of the "bigger" objectives (44 & 50mm). Often times those require taller scope rings. By using the higher mounts, it puts the scope "line of sight" or sight plane even higher over the top of your barrel's firing plane. This will exagerate the "rise" and "fall" of your bullet. Stay with the 40mm objective and you'll be happy and should be able to use your existing rings / bases.
You will be happy with the clarity and light transmission of most of the modern scopes once you jump up to the $150+ price range. The more you spend, the better glass, lens coating, etc.
Good Luck
John