For an adjustable water bottle cage see:
https://www.amazon.com/Topeak-Modula.../dp/B00GHR56W2
Topeak Modula EX Bicycle Water Bottle Cage - $5.50 each.
or
http://www.chainreactioncycles.com/t...2/rp-prod68036
Topeak Modula Adjustable Bottle Cage 2 - Sterling 9.49

As the Good Book says, "Seek and you shall find".
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Cheers,

John B.