Came across this today buying envelopes. It may or may not interest you but i just had never seen a seller with 1million+ feedback before. So i thought i'd share it.
http://www.ebay.co.uk/itm/MAIL-LITE-GOLD-PADDED-BAGS-ENVELOPES-ALL-SIZES-ANY-QUANTITY-/150668484797?pt=UK_Envelopes_Mailing_Bags&var=&hash=item23148aa0bd#ht_3023wt_1189
http://www.ebay.co.uk/itm/MAIL-LITE-GOLD-PADDED-BAGS-ENVELOPES-ALL-SIZES-ANY-QUANTITY-/150668484797?pt=UK_Envelopes_Mailing_Bags&var=&hash=item23148aa0bd#ht_3023wt_1189