Stuart,
The Koka noodles that you see in supermarkets are actually ramen noodles - they are just not labelled as such. You can get Ramen noodles labelled as such in health food shops but the price is greatly increased for the privilege.
I usually feel silly going into those shops just to nose around with no purchase in mind.
There's a shop also at the Jervis outbound Luas stop which might stock these.