Would it be possible to modify your existing $38 737NG MCP into a 747, 757, and 767 style MCP like the graphic below? Sourcing the MCP seems to be a problem right now, especially one as easy to manufacture for the home user like yours. Would definitely be willing to compensate you for your time given the changes required. Good news is that would cover those three classes of aircraft and get quite a bit of use I would imagine. It kills me that I can't seem to find a suitable download.