You can get a ceramic platen from Ellis
http://elliscustomknifeworks.hightemptools.com/index.html but it might take a while...
I had mine made at a local glass place. The stuff Ellis sells is just high temperature ceramic glass that is used for woodstove door windows. Cost me less than $2.00 to have a piece cut. There are probably other places that carry pre-cut stuff too.
Mine is JB welded to the platen that comes with the machine.. and then I have two set screws going through at the bottom of the ceramic to form a ledge. Some people think this is unnecessary. If you search Blade there are several good tutorials on how to do this.
Okay.. here are some pictures. You will have to forgive the 'craftsmanship' when doing these mods.. They were usually done in the heat of the moment when I realized whatever the limitation was. I'm also not saying any of this is necessarily safe.
Here I cut away some of the guard to expose the contact wheel... this allows you a little more room to do stuff as well as use the radius of the wheel.
This is the back of the machine. I had to cut away more of the guard to give me room to use the thick 3M scotchbrite belts.
This may be hard to make out.... but this shows the edge of the ceramic platen and where I had to cut away some of the original platen to allow me to use a file guide for setting my plunges. A crack has just formed in the ceramic for some reason which you can see... I will probably just remove it all together because I now only use this for hogging wood and sharpening.. hence the leather belt.
Sorry this isn't all that clear.. but like I said..if you search the Blade forums you will see detailed tutorials on how to do the platen. The other stuff are just things you do when you realize they need to be done and are not afraid to grind things away.
As to belts... Trugrit has been the best source for these sizes. Most knife supply places don't carry much for 2x42 but Trugrit carries all the Klingspor and Trizact CF.. both of which I recommend. With a blue 36 grit Klingspor on a this lighting fast apparatus.. steel flies so make sure you are confident with what you are doing.
Hope that helps!