Who sells parallel ports anymore? I don't think the transfer cable from 1541 to parallel port will sell because most people would have to have a parallel port installed on their computer and do they even make them anymore? Does anyone still know how to use them?
If you want to sell then you have to update your products.
I have a 1541 hooked up to a parallel port, to write d64 images from the internet. It works really well. I also have a small laptop hooked to my C128 via a parallel port, and run 64HDD, which means I can mount any drive or directory on the laptop as a floppy disk on the C128. I don't throw away any old PC, and pick them up for nothing at yard sales, and here at work, when they retire them. Very cheap, and they still have plenty of good uses. Most people, when they get a new PC, just want rid of the old. Bad for them, good for me.