How many dollars equals 40 pistoles?

Alexandre Dumas relates that 100 pistoles are worth 1,000 livres tournois (The Three Musketeers), which share a 1:1 relationship with the livre (wikipedia). A pistole, then, shares a 1:10 ratio with the livre.

An unskilled laborer in 1650 earned 1 pistole/diem (10-hour days). Because the work days were 10 hours we can conclude that an unskilled laborer was paid 1 livre/hour. (Gerry Lalonde, MONETARY VALUES IN 1650 - 1750 IN NEW FRANCE COMPARED TO TODAY)

The 2009 federal minimum wage is $7.25/hour. (infoplease.com, Federal Minimum Wage Rates, 1955-2009)

So, we could conclude that:

40 pistoles = 320 USD

However, remembering cost of living... (Gerry Lalonde)
4 lbs of bread in 1650 cost 4 sols (2 livres - $14.50)
1 lb of butter cost 12 sols (6 livres = $43.50 today it costs $2.80)

Whereas in 1650 it cost about 3 livres a day to feed a man (or 30% of his income), today between 19 and 25% of income is spent on food for those earning under $20,000/year (www.ers.usda.gov) - and a loaf of bread doesn't weigh 4 lbs anymore. So, take these rough calculations for what they are worth...I'd say 40 pistoles is worth roughly 300 bucks in 2009 and 2009 only...the value of the dollar changes more than ocelyn Wildenstein's face, so who knows what 40 pistoles is worth an hour from now.