Accelerator cable
Alternator belt
One front wheel bearing set
Tools, all metric, sockets, wrenches etc.
Duct tape and electrical tape
Spare fuses (they are unique to vw/porsche...not easily obtainable on the road)
Spare relays, but we can get you around that.
A metal coat hanger...cause its so very useful.
Spark plugs, points, cap, wires.
Carb cleaner (if carbed)
Wire cutters, pliers etc...a basic full blown tool kit.
An aluminum floor jack
Grubby clothes
A mat to lay on at the side of the road
Vice grips
A smart phone or tablet with internet access to reach out for help here.
At the very least, there should be someone within a few hours of your breakdown that might be friendly enough to come help you out.
Most of us have at least two cars worth of parts
If you are nervous about it, post the details of your trip ahead of time.
People are really cool here and may volunteer to be on standby.
Good luck with your trip.