Type Of Envelope Used By USPS For FDCs And Dcps

Hello,

I would like to purchase envelopes similar to (or preferably identical to) those used by USPS in making FDCs and DCPs of their new issues. Any tips/advice?

The reason being that I would like to mail for some pictorial postmarks and would like the look to be similar to those I purchase from the USPS store. I know USPS recommends using "envelopes of 80-pound Accent Opaque, acid-free, 9/16-inch side seams with no glue on the flap." However, I am not sure if that matches the envelopes used by USPS for making FDCs of new issues. Also, I don't know where to buy them.

Thanks for the help.

Check this out:

http://www.uscs.org/online-store/cover-supplies/

Thank you...that is exactly what I was looking for.