It's simply not cost effective. To do a one off set it would be something like $60 for the keycaps set plus about $3 per key for dyesubbing or in other words $372 for ONE keycap set. Of course the other big problem with PBT is lack of ISO enters from most sources, and lack of keycap color selection without very high production minimum orders.
That G80-3000 in purple, it's just stock lasered keycap. I only dyed the key solid color myself.