Hi guys! After an unreasonable amount of hours, I finally made it back home from Hamburg.
On my travel there, I managed to take a look at the TAG Turbo F1 1,5L motor which included K26 turbos. Thought this info might be a nice addition here.
K26-3067GGF/8.11
86 943 0064
5326 999 1174
Compressor housing reads
(86) 5327 101 50(74)
So all in all, it seems a K26 hot side with a K27 cold side.