As Sebastian pointed out, this kind of financial information is highly guarded. You should, however, be able to make a generic analysis. It should be pointed out that Mast Bros operation is completely different from Torres - small vs. large factory.
First, what is the price of beans? Bean to bar makers are paying higher than Fairtrade pricing so estimate around $3500/ton. Add in the cost of shipping - $400 per ton. And the cost of sugar - Organic sugar is $2/lb. These are the raw materials.
Now processing: the beans must be sorted, roasted, cracked, winnowed, ground, counched, tempered, molded and packaged. For small batch operation that might take two people, 20 hours and produce 100 lbs of chocolate. For large factory like Torres - no idea as it is a highly automated process. You will have to research the typical cost of employees in NYC.
Equipment: A small factory might have $150,000 in equipment - a large factory $2-$3M. A portion of the cost must be added in along with all the other overhead - sales, marketing, IT, wages, taxes, websites, packaging, maintenance, travel, utilities, etc. Overhead could run 500 - 1000% of the cost of the beans.
From there you can derive the cost per bar - with plenty of assumptions of course. Most of the costs are variable and controllable by the company.
Or use an industry estimate - one book on specialty food retailing said that the typical retail food cost was 35% of retail so a $8 bar would cost $2.80 to produce.
Hope that helps.