Depends on the volume of course, and of the quality of image that is expected. This board, plus transducer (necessary to get the image) in small volumes, should be around 200$. Maybe less in higher quantities, and with streamlined components. Far lower than the usual portable ultrasound scanners (costing ~5k$). But that's a work in progress so let's see!

We were following the Newcastle project, but I guess the tech was finally bought by NDT -> image quality and framerate were not as good as expected. At least, haven't seen progress on medical imaging use from this end.

Done, tried to write a summary on the home page, thanks for the feedback!