Humm .... I didn't run across any model numbers. Is that the convection oven/roaster or the convection coffee roaster? Who makes it? Do you still have the instructions that came with it? Maybe, the box it came in?
Ok - just to make sure we're talking about the same thing ... is this what you're talking about?
These was made in China and marketed under several names. If you're talking about the knob on the top ... you might not find an "exact" replacement but you can probably find a "make do" replacement at a local RadioShack store or a small appliance repair shop.