Pricing is likely set by estimating the number of sales, and then amortizing the development and tooling cost. Then, the cost of components assembly and testing. A reserve is created for warranty cost.
Advertising, cost of salesmen, transportation, cost of money for keeping a stock in inventory, etc is also added in.
Its likely that the amortized cost of development and tooling is much higher for lenses that sell only a small number of copies, and the cost of special one of a kind or limited production components is also very high.
Then, there is profit. Canon likely makes much of their profit from lens sales, and sell bodies for a small markup, knowing that owners will then have to shell out for lenses.
I'd expect that the actual cost of production was a small part of the final selling price.