Implement a list of Inventory Item with user defined pricing

I have a custom record ("Insurance Carrier") and on these records I need to have a list of inventory item and pricing.  To explain:  We charge a different amount for our products depending on what insurance our customers have.  There are too many options to create pricing groups to accomplish what we need.

What I would like to have is a 'Machine' (like the line item machine in the sales order) that would allow me to choose an item, then in the next column enter a price for this item.

I will need to define several of these items for each insurance carrier record.