EPCM allocation from parent to child, is it possible in only one allocation rule?

Summary:

Let's say we have a product dimension with 2 levels: brands (parents BRAND 1, BRAND 2, BRAND3...etc) and products (lev 0)

We need to allocate some costs we have by brand, to its products using sales driver. 

Since EPCM works with ASO, we created some fake products, one for each brand, to load each brand's costs.

As an example

BRAND 1: $100

BRAND 2: $300

BRAND 3: $0

---------

BRAND N: $500

Is it possible to create one allocation rule to allocate all brand costs, from each brand to its products?

If we select TotalProduct as source and "Same as Source" as destination, it doesn't work since we don't have sales in our fake products, but in real products.