Silicon Valley’s teardown analysts these days don’t even wait for the body to arrive before publishing their autopsy reports.

Case in point: the estimated bill-of-materials for Apple’s (AAPL) iPad issued Wednesday by iSuppli, an El Segundo, Calif., company that specializes in so-called virtual teardowns.

Retail prices for the device, which is scheduled to start shipping in March, range from $499 for a 16GB Wi-Fi-only model to $829 for a 64 GB version that also works with AT&T’s (T) 3G network.

Using the components described in the product’s spec sheet and making educated guesses about who might supply them, iSuppli produced the grid posted below the fold.

Based solely on parts and manufacturing, iSuppli estimates that Apple’s mark-up ranges from 117% for the low end unit to $147% for the high. The most profitable model would appear to be the mid-range, 3G-ready 32-GB iPad, with a sticker price of $729 and an estimated manufacturing cost of $287.15.

Below: iSuppli’s bill-of-materials and manufacturing estimates.

Note that these estimates do not include R&D, patent-holder royalties, advertising or any of the other costs associated with bringing a high-tech product to market. But it’s worth pointing out that Apple’s gross margin — 40.9% last quarter — is one of the industry’s highest.

You can read the company’s footnotes and detailed parts rundown on its website.

See also:

• Could Apple iPad prices fall?
• The myth of the free iPad

[Follow Philip Elmer-DeWitt on Twitter @philiped]