I have a product that I manufacture.  Some of the components used to build the final product can be from any number of vendors.  I stock each of these vendors parts based on availability.  

The final product I manufacture is a widget and orders are for the widget regardless of which vendors parts were used to build it.  But I want to keep separate inventory for the vendors parts and be able to order them as needed.

I don't want the sales orders to specify which vendors parts simply X # of widgets.

I initially thought to use variants, but it seems I have to have separate BOMs for each variant, and the sales order needs to specify the variant in the order.  I tried to make variants for the components, vs the final product, but I can't add a component to the BOM that is not variant specific.

I want to have a BOM where the component used is one of any of the variants depending on availability and stock.

Is this possible?