This might help you with your KX-830. So far, I've not been able to locate a complete Service manual for the KX-1030. I assume the KX-830 and KX-1030 have some interchangeable parts.
I attempted to upload the file, but this site responded that the files were too large. Here is a link to their location. The KX-1030 Service manual listed is not the Service manual (mainly schematic and parts list), or it is missing key pages concerning servicing the unit.
http://www.vintageshifi.com/repertoire-pdf/Kenwood-12.php
Hope this helps with your pinch roller replacement (pn's should be listed).