The '06 can be bought in 150 to 200 grain loads for cheap. Every where I have ever been.
270 is usually found in the 130 grain offerings for factory stuff in these parts.
243 can be bought in the 100 grain offerings here.
7mm-08 in 140 grain stuff is quickly gaining ground on these three for factory stuff around here.
Personally, I own the first three. If I had to choose only one it would be the '06. It's the one gun solution for any game in NA. From 110 grain varmint loads, up to the 180 grain reloads over top of R22 nearly matching 300 win mag velocity's in a shorter barreled, lighter gun. It is the most versatile cartridge every designed. It does this in a reasonably light, compact, accurate offering.
I like my 243's and my 270. But, it ain't the '06.
As the thread proves, many opinions exist. None are wrong Some are just not quite right fo the OP. The 260 would have been dead had it not been for the long range guys. 6.5 anything is expensive because demand is growing. You could go 308 and meet the requirements of the OP. 6 mm is like the 260. A great caliber that just didn't catch on with the hunting crowd. 280 is a good one but hard to find. 25-06 is going to come with a long barrel. Etc.... The one thing that can't be denied is the availability and function of the top 3. 30/06, 270, and the 243. You really can't go wrong with any of them. It is region specific but, I imagine the 7MM-08 is gaining ground out there too. It's a good'er one. It is to the 270 what the 308 is to the '06. Nearly as powerful but, comes in a lighter, short actioned rifle. Ain't it fun to choose.
God Bless