i found a coolant leak on the bulkhead where the pipes to/from the engine connect to the heater matrix. does anyone  know the part number/ where to get o rings/new pipes from.

 

I noticed the bracket at the top of the pipes has fatigued and failed. I suspect this is why they have started leaking.

While I still haven't actually fixed this, I hope this helps http://www.briskoda.net/forums/topic/308308-heater-matrix/?hl=%2Baluminium+%2Bpipes#entry3690590