Hi Catherine, hope one of these helps! Good luck 🙂
* The gray Peace from Envelopper Ink is a beautiful light gray: http://www.envelopperinc.com/mm5/merchant.mvc?Screen=PROD&Store_Code=ENVLPR&Product_Code=A7122
* Nice light shades, and love this company – almost always ship the same day:
http://paperworks.com/store/products/classic-laid-envelope-antique-gray-a75-14×7-14-250box
http://paperworks.com/store/products/royal-fiber-envelope-a75-14×7-14-gray-250box
* Paper Presentation has about 2 or 3 different grays: http://www.paperpresentation.com/mm5/merchant.mvc?Screen=CTGY&Store_Code=PPN&Category_Code=A7B