Re: I wouldn't call it "Linux despair" ...
Most modern barcode readers pretend to be a USB connected keyboard, even the cordless dongle ones, and there are also variants which act as a Bluetooth keyboard (I have two of those, and they tend to also read QR codes as they're camera based, not LED/laser scan). Most of these can also be programmed to hit Return after a scan.
So, as long as your software uses keyboard input routines it should not be hard to replace the barcode readers with something from Amazon.
Look for the name "Netum" - they tend to be reasonably well documented and are usually in stock.