I've seen both of these but can't remember much about them. The black one was sold as an extensive package to start your own sign business. I had a brochure once and I think they want $12,000 or some outrageous amount, but that may have included licensing fees or something? The company was called "Elite" or "Prestige" or something fancy?
They are all out of business now, there were many of these back when magnetic signs were popular. They are designed to form thin styrene and have limited forming power (vacuum cleaner motors), and limited clearance because they only formed shallow parts.
These old sign machines aren't really too useful for anything other than blister forming for packaging uses. I used to buy them up, then upgrade the platen and vacuum system and raise up the oven to allow more depth. Its really easier to just build a good one from scratch.
They are still good for demonstrating the process and are often used in schools. Sorry I couldn't be more helpful