Custom letterpress or foil printing is currently booking about 5 weeks out.
Colorplan's Stone envelopes
A7: 5.24"x7.25" - Deep Euro Flap
Price is per envelope so you can order what you need.
2ply Coaster Stock - Blanks
Amethyst Envelopes
Azalea Stardream Envelopes {Pearlized}
Azure Blue Envelopes
Baghdad Brown Envelopes