What sort of hinge is this?
From what I can tell these appear to be hinges made by GRASS. A look at an online retailer seems to point to these hinges:

http://www.hardwaresource.com/hinges/cabinet-hinges/blum-european-hinges-grass-european-hinges/grass-european-hinges/grass-830-and-831-hinges

However the above appear to be obsolete and they recommend replacing with these hinges:

http://www.hardwaresource.com/index.php?l=product_detail&amp;p=3987



These appear to require two separate order parts.