ahh ok. Sorry, I thought the price you gave me was including postage...
Hopefully it's not too much.
If you put them in 2x 5card toploaders, then into a medium sized bubble mailer, you can send that for $1.40 plus the 90c for the mailer.
if you put them all in separate top loaders, it will get costly due to the thickness.
Let me know how you go