May I ask from where you obtained the yellow key caps please?
Are they really exactly the same colour as Filco yellow?
And are printed ones available?
Greeting. I can assure you the yellow color is 100% the same as the Filco yellow. It
IS the Filco yellow.
Long story short about the source of these key caps: I live in Taiwan. You might already know, even though Filco is from Japan, the Majestouch products are in fact manufactured and assembled in Taiwan by Costar.
The vendor from whom I bought the key caps is able to make direct contact with the key cap supplier of Costar, that's how I obtained the yellow key caps.
As for printed ones, that could be arranged as well.