Invitations-Where can I find Heavy Ones/Fabric Ones?

I was recently at a friend's house and she had gotten a VERY EXQUISITE invitation to a wedding this summer...the invite was heavy paper with a fabric inside, and the letters were either engraved/letter pressed (not sure)...I am sure they cost a fortune but was hoping there is a website someone can recommend to look at these types of invitations...I tried Precious Collection, but they seem to only sell simple ones....TIA!