I wish i thought of that. Not only would I have had my something blue, I would have matched my bridesmaids. I say do what makes you happy. It kind of reminds me of Cinderella and the glass slippers.
There could be one problem though. If they were not originally light blue but dyed to match the dye tends to run and can ruin your wedding dress. Especially if the ground/grass is wet. So I would only do it if you can find light blue heels.
I found these - some are really expensive (nearly $300, and some are reasonable $45) - but you seem Ok with a high price if you like them. Hope this helps.
http://www.zappos.com/n/p/dp/24372293/c/102801.html
http://www.zappos.com/n/p/dp/32150109/c/158.html
http://www.zappos.com/n/p/dp/32342736/c/98916.html
http://www.zappos.com/n/p/dp/27076662/c/11003.html
http://www.zappos.com/n/p/dp/26677053/c/5039.html
http://www.zappos.com/n/p/dp/16211587/c/79835.html
http://www.zappos.com/n/p/dp/22696232/c/1137.html ( i really like these, they are dressy & have white and silver incorporated in them)
http://www.zappos.com/n/p/dp/32321723/c/50373.html
http://www.zappos.com/n/p/dp/10045704/c/50759.html
http://www.zappos.com/n/p/dp/23856066/c/605.html (last 2 like cinderella's glass slipper!)
http://www.zappos.com/n/p/dp/20512831/c/82605.html
http://www.zappos.com/n/p/dp/32386863/c/69965.html
http://www.zappos.com/n/p/dp/32310962/c/5853.html