Originally Posted by
non-fixie
A similar K seems to have been used by Ken Evans for a while. Less likely candidate perhaps, as it's an Australian builder. And the frame would probably have had 'Kenevans' dropouts.
That was my first thought, but as you mentioned, the rest of the frame doesn't tell the same story. I believe Ken's frames have a four digit serial. Still, could be a Kenevans fork.