I have got a blank
Leopold ANSI set on my Ducky TKL.
It is in Cherry profile and in thick PBT, which could be hard to fit on the stabilisers of some early-generation Filcos. The colour is also a very dark blue, which is hard to match.
Because it is a full-size set with number pad, and comes with an additional 1.25 key (really intended for the printed versions of this set that supports both Fn and Menu on the right), it means that the only key not included for an ISO TKL is the Enter key.
I use an original Cherry PBT lasered Enter key that I had dyed with Royal Blue
RIT fabric dye.
The RIT dye did not take at first, but I experimented by adding some vinegar and then it worked.
The bad part is that the lasered legend shows.
I am looking forward to when someone starts a group buy of blank Gateron ISO Enter keys. I have only heard rumours about it so far ...