there are a few different ways to do this:
1) You can create one product that is the package
2) create a discount that is triggered by having the 2 items in the cart. for examples sake, lets say the IDs for the 2 items are 1 and 2, On the discount tab of the eCart object create a new discount and set the triggers as:
"Presence of item In Cart"
If item '1' 'exists' in the cart
If item '2' 'exists' in the cart
the set a flat rate discount that would make your total equal 99.