Recommendation for my .17hmr set up?

[leadpig]

30mm tube biggest bell end you can find lets more light in...myself mtc viper 56mm works nice lowest zoom at night...your not shooting long distance in the dark so it makes little difference

tube size is irelevent and only important for dialing,bigger the tube the more clicks ect
the human eye can only focus about 7mm of light,so if you had a 25mm and a 40 mm scope by the same manufacturer with the same mag ect the light would be the same.
it is the objective end that gathers light

[1in9]

You can get a second hand Leupold on eBay for that sort of money. Excellent build quality with a lifetime guarantee, significantly better optically than a new Hawke, Bushnell or similar in the same price range.

I would go for as higher mag as you can get, .17HMR is all about precision at 100m. A Leupold 4.5-14 or 6.5-20 x 50 (or x40) would be just the ticket.