Yes, I have some more for you, this time proof printings for the 1933 Kreisler set, issued in the Netherlands Indies. They (Enschedé that is) started off with proofs of just the portrait. These exist in eight colours and in small and large format. Here's a large format example.
The same proofs also exist perf 13, like so:
The final product had decorative borders on both sides and looks like this.