The colors like old IBM and Cherry keyboards?
Yes, those that don't feel pompous, are clean and high-contrast, are visible in dim light, and just DO THE JOB.
Ivory - was that the IBM color?
And the text? Centered or off-center?
Whatever SP could do properly.
If there is a designer on this forum who would prepare SVGs for 104/105 standard sets, maybe we could swallow the $25 setup per key and have proper font, trace width and positioning. If SP don't rescale/shift the images. But this could be avoided by providing a guard trace (in another color?) for their reference.