Bad idea or not I think Trevor is more interested in the look that optimum functionality. Those look just like the hydraulic lines found on German and French built aero engines and aircraft from the 1940's - 1960's, the goldish colored ones are reuseable, not sure about the silver ones, they look crimped. I'd search up some vintage European aero engine rebuilders for you, but the language barrier is more than I feel like dealing with right now so you'll have to do that yourself. Find a few and ask them where they get thier lines and fittings, don't rule out eastern European makes as well, many Czech and Polish engines use very similar stuff.
There's some serious restorers in the vintage aero game who can find or reproduce any part for a 100% correct restoration regardless of how old or rare it is, all you need is a fat enough wallet.