Research firm iSuppli, known for its teardowns of devices like smartphones, recently took apart a stab at estimating the cost of building Palm’s upcoming Pre smartphone. It estimates that every Pre costs around $138 to build.

That’s less than half the $300 or so that iSuppli thinks Palm and Sprint—the carrier to offer the Pre—will ask for the smartphone. By contrast, it costs about $203 to build a BlackBerry Storm, which is offered by Verizon, and $174.33 to put an iPhone 3G together.

Keep in mind, until iSuppli actually gets a Pre in its hands to take apart, there’s no real way of knowing for sure how much it costs to build Pre. If the estimate is accurate, however, then Palm could be looking forward to a healthy profit margin on the Pre.

The Palm Pre is supposed to ship during the first half of 2009. Nobody knows when exactly, however.