POINT 1:
You can have multiple suppliers per item.  In the item, there is a Costing tab.  In that tab, you can list all of the possible suppliers for an item.

POINT 2:
In Supplier preferences, there is an option "Filter items according to suppler".  If you turn this off, on a Purchase Order, the list of items will not be limited to the current supplier.

David Nelson
Dynamic Enterprise Technologies Inc
Seattle | Portland | Los Angeles
www.dynenttech.com

Read More...