Nope, you need some more money. A 6-18X scope of any quality is going to cost you more than $150. You will need at least another $100 to get you into a Bushnell elite 3200. A decent varmint scope starts at about $250 and goes up from there.

You also can't have your cake and eat it too. You can't expect to have a 6-18X scope paralax free at 20 yards. It isn't going to happen.

A 17HMR isn't a long range cartridge. You will have better results for your wide range of criteria with an all around hunting scope in the 3-9, 3-10, or 3-12 power range. Another plus is that with lower power scopes you can get a much better scope that is much closer to your price range.