Hi Bill
I can confirm that the MPCC does a great job on my SN10. I can see no reason why it would not work on the SN8 as it too is f4. There is some evidence that, because the SN scopes are already corrected, the MPCC will produce an overcorrection. If this is indeed a problem it is not noticeable in normal visual use or DSLR imaging.
I got mine at Alpine Astro as well. Here is a link to the info:
http://www.alpineastro.com/optical_a...ccessories.htm
You will be up for around $A200. There are prices on the site.
Hope this helps
Cheers