Hi, Matt here and create d3.js charts for you (webmaster for 22 years, scripting javascript/web animations and visualization last 3+ years).
Please send more detailed specifications yet I understand what you need. I assume Drupal API work is not required (am still administering Drupal 6 website), only javascript work.
For the responsive d3.js proof of skills here are two charts, one mine personal, the other for a client (mask of a mask :-), captions are removed at small screen widths, was a proof of concept and client hasn't wanted to develop it further):
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Looking forward to your reply,
Matt