Not sure if any of the major sites do that ... there are lots of sources for stock photos but if you want to sell stock photos, I'd think you could just set up a stock photo site and promote it to the photography community. People looking to make money with their cameras would flood you with content that you're buying directly from them, no need for a 'wholesaler' in the middle right?
Anyway, below is a list of stock photo sites from which I've sourced images for my projects. Some are free and some are paid, and some are better quality than others.
Frank
StockXpert.com
istockphoto.com
canstockphoto.com
bigstockphoto.com
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pixelperfectdigital.com
intuitivmedia.de
photocase.de
bigfoto.com
creativity103.com
freestockphotos.com
openphoto.net
picswiss.ch
laterramagica.com
photospin.com
webshots.com
imagepoint.biz
gettyimages.com
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