While I'm no longer with High Roller Games, I can tell you that when I created these mats they were set at the correct size for printing. You may want to check your file print settings and see if any scaling is currently occurring (pdf's are often automatically scaled by printers). If it is, take scaling off and re-print.
If that doesn't work, you may want to send High Roller Games an email, as I don't know if they made any changes to the original files since I left.
Hey, thanks for your reply. It is not a scaling issue, the file size/resolution is simply too small (they are also named "...preview"). I sent a mail to HRG, and they said they would get back to me, but that's already half a month ago. Still, I sent them another mail today.