I can offer any diameter & length you may need of the latest Multi-fuel hose from Cohline in Germany.
I make up custom fuel & oil hoses & lines for the early Porsche models and keep just about every fitting that may be used on a Porsche in stock.
Also keep in stock Metric braided SS for those who desire bling...........
Len at Autosportengineering dot com
PS- Note for RWebb - perhaps you might also like to know............, I make a permanent Fuel Tank Vent Fix kit for those of us who own Vanagons and are paranoid about fuel tank grommet leaks.