Hi I've had a quick look and theNNN-NN-NNNNL fits a Polo so it's no good for you but theNNN-NN-NNNNJ should be the right one for your golf so I would opt for this one.
I hope this helps and if I can be of further help please feel free to ask
According to my computer that ECU is for 2002 onwards but this doesn't mean that theNNN-NN-NNNNJ has not been superseded to the later part number. They both relate to the AQM engine which is hopefully the engine code you have, this should be in your service book.
I would fit the ECU for you but they need to be coded to the car by a VW dealer due to the immobilizer system. If you just replace the ECU your car won't start so they would end up having to do the whole job I'm afraid.
Hi Nick I've been having a look around and it looks like it will have to be theNNN-NN-NNNNS ECu for your car with that engine code. The one for the Octavia isn't listed for any VW vehicles. The best I have done is find a ECU at £179 plus P&P or you can try BBA Reman who may be able to repair the ECU that you have.
Sorry I can't help much more than this but I hope you find one soon.