Have you considered screw on close up filters? Hoya makes a good set of 1 2 4 that I have in a 67mm size; I tend to purchase the filters to fit the largest lens I have, then buy stepping rings to accomodate smaller filter sizes on other lenses. Definately in your price range.
Then you don't have to buy a bigger bag to accommodate more lenses/other crap like me. 
~Tiff
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"Were the diver to think upon the jaws of the shark, he would never lay hands on the precious pearl."

