the 3-9x40 size would be my suggestion. As for brands, wow, does that open a can of worms.
Some I've had in that price range that I would have again:
These just to name a few.
Some I've had that I would NOT have again:
Any of the no-name cheapo crap
The suggestion to check out SWFA's sample list is a good one as is keeping an eye out on the trading post here.
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