I'm pretty sure that either the "PERB" would need to be so massive to get enough of a pressure differential to cause lift that the FAA(USA) or CAA(UK) would require you to jump through very expensive hoops, and also that I struggle to think of a material strong enough to hold an almost-vacuum yet light enough to lift off! Also bear in mind that any payload and recovery system is likely to weigh upwards of a KG...

For my money: just buy a weather baloon for £15 on ebay and get a cheap cylinder of helium from your local welding supplier and you can be on the edge of space within a couple of hours!