Is there a device that you can place at the end of a high volume valve to test the vacuum flow at the tip

Hi Martin,
There is a product on the market that I have seen, however it is pretty pricey at around $500.00.
A tool like this has been discussed recently here at DCI as a possible new product.  Our idea was a tool that would attach to the end of an HVE and be able to show both in/Hg and a flow reading in cubic feet.  Would a tool like this be useful for you if it met a better price point than the other option?