I'm not sure if they were Kunifer, but back in theearly 90s, I put "copper-alloy" brake pipes (sourced from either AH Spares, or SC Carburettors) on my car and regretted it. They were very soft (which did made them easy to bend) and easily damaged.
A few years ago, I replaced them with a full set (I mean EVERY pipe) from Classic Tube
https://www.classictube.com/
While I opted for stainless steel, they also do mild steel as originally equipped, if you're going full concours.
They come pre-bent, and fit very well with only minor tweeking. The longest tube (4-way to rear brakes) was bent in half with a large-large radius and was easily straightened.
I was able to install them in a fully assembled car with a minimum of fuss.
Some details:
https://www.rfdm.com/gallery/album51