So I have been in contact with a gal who is having a horrible time trying to find mailers to fit her custom invitations. This seems to be the most significant and often overlooked part of the DIY process. You have a gorgeous idea of what you want for your invitations... you spend $$$ on all your supplies, and tons of time painstakingly crafting them. But it is all worth it because you have the perfect one-of-a-kind invitations. But wait a tick... how do you get them to your guests? They don't make an 8" x 8" envelope? Or a 7.5" square mailing box? This is a panic moment because your options are expensive... custom boxes or envelopes.
I always advise my DIY brides to make sure they can find an envelope or mailer for their invitations before they order custom silk panels or silk folios. And though it may seem like your options are limited to boring envelopes or ho-hum corrugated mailers, look for awesome presentation pieces, like this damask packing tape from http://www.paper-source.com/