The KN7000 is currently changing hands in UK for around £800, which at the current exchange rate is about $1270 Australian.
You must use Standard SD Cards NOT SDHC card - The KN7000 operating system will not recognise these higher capacity cards - they were not around when the KN7000 was designed and they use a different addressing system to the Standard cards.
It is true that the Standard SD Cards are becoming scarce but they are still around - but mainly at the higher capacity level i.e 1GB and 2GB - do a Google Search......
In UK, it seems that most are available in Micro SD format, (for mobile phones etc.) but that is not really a problem since that variety usually comes with an adapter which converts the Micro format to the standard physical size.
Exactly the same foot pedals as used on the 6500 - both single and 4 Way versions - are 100% compatible with the KN7000 as is a Swell pedal which works with the KN6500.
Your 6500 disks will also work fine in a KN7000, although you may have to do some minor 'tweaking' of the actual sounds. Most of the time, this will not be necessary.
Hope this helps Jean