so i just bought a portastudio 424 mkiii for £30 (which is an amazing price) and i need some tape for it. it says i need type b tape (such as TDK SA) and that it needs to be 90 minute tape or less, preferably 60 or less. i found some tape on amazon, but i can only get TDK SA as 90 minute, not 60, so i was wondering if is there anywhere else which sells tape that i should try that might have such things?