sorry mate, been ages since ive used a standard oil cooler, and I just used all the standard fittings so didnt need any.

I think I used a flexi pipe from halfords of all places for the hose from the rad to the plastic pipe that comes from the back of the block round the front under the pipe that goes into the head, if thats what you mean?
Doesnt need to be anything specific, anything that fits will do, and doesnt even matter if you go up and down in size a bit, I was running my LET in the back of mine to the radiator in the front via a bit of 19mm copper tube 6 foot long and the water pump still didnt give a fuck, you cant really go wrong with it mate