No worries. I know what it is like to put together masters that need to be shipped out either to a production house or to end users. You have to be extremely careful with every step, down to the premaster codes, if needed.

Does any of your existing / remaining media specify what kind of die it is? You might be able to google on that to see if anyone is selling that type of media at a good price.

Sorry about the 80 minute comment. I thought that some of the manufacturers had started playing around with the spacing of the guide grooves. CD Recordable used to have an excellent tutorial of CDR manufacture at one time. They have since taken it down. In any case, they may be another good source for various media types.