Excel 2007 : Using sumif with variable multipliers

I'm afraid there is an obvious and simple answer to my problem but I'm just not thinking of it. Here goes:

I need a formula that provides the results of a sumif formula but has each component of the total multiplied by a factor that could vary for each item. Perhaps it could also be described as a sumproduct applied only to specific records. For example, in the two tables below I want to find (sumif?) the total of "C" as a taker in the top table times the tax rate of the givers shown in the bottom table. The answer expected for "C" is 90 (50+45). I need a solution that does not require adding a seperate column to calculate the tax for each row because the actual application of the formula will be in a large complex model that doesn't allow the necessary extra columns. I can't seem to nest a vlookup or other formula within sumif but I'm not convinced this is the answer anyway. Please help with suggestions.

giver taker value
A C 100
B C 60
B D 75

Player tax%
A 50%
B 75%
C 33%
D 20%