Just googled for prices of 3D printers. I thought they cost too much for someone who can't profit from their use. It turned out that I was very wrong, and that they don't cost more than many other tools people have and use rarely, like electric drills etc. See for yourself. They are really affordable, especially those that can print only smaller objects which is actually what boombox collectors really need for replacement knobs, sliders etc.
Perhaps it would be good idea for Boomboxery owners to get one, and offer printing of parts as a service. An invenstment that would payoff itself trough one or two orders, and than just keep on briniging money thus increasing popularity and visits of the site. The need for the replacement parts will exist as long as collecting exist, and who has the better knowledge and possibility to 3D scan and copy part from original one?
http://www.3ders.org/pricecompare/3dprinters/