I have some of that stuff around the oil temperature sensor and associated wiring/plug in my sump as it’s next to the crossover pipe.
ATEC in Brackley sell both types, I found them after searching a part number I could see on the metric hose sets that Lindsey Racing sell.
I got some AN hose to metric fittings from them which are superb quality (made in Germany). They appear to supply to the motor racing industry mainly but are happy to take orders over the phone with a card. Their catalogue is extensive and can be downloaded at the link below. I think these metric fittings may connect directly to the factory fuel lines (as well as fitting the damper, rail, and fuel regulator connections), need to check next time I have the bonnet / hood open.
I ordered the following so far - (series 400 for standard braided rubber hose, series 600 for PTFE hose)
1 x Series 400, 00 degree Metric Hose End, Dash 6 to M16 x 1,5 (643.012)
1 x Series 600, 00 degree Metric Hose End, Dash 6 to M16 x 1,5 (642.065) - ordered in case I end up using PTFE hose for the main engine bay lines
2 x Series 400, 90 degree Metric Block Swivel Hose End, Dash 6 to M16 x 1,5 (643.044) - these are for the fuel jumper line
Will probably order my hose from them when the time comes and some standard AN fittings if required. Feel a lot more confident about the product reliability and safety vs ordering off ebay.
ATEC Autotechnik GmbH – High Performance Fluid Transfer Systeme
atec-autotechnik.com
You can also order a printed copy of the catalogue.
They have a backdrop on the web page featuring the Formula-E Porsche car, so they possibly supply Porsche with fluid fittings.