Hi Folks.
Just wanted to post a follow-up completion comment on this repair.
The parts arrived from the US very quickly. The seller included both of the oil pipes, plus the banjo bolts and a full set of washers. The condition of the pipes, given that they were second hand, was outstanding. No sign of rust whatsoever (they came from Kansas in case you are interested). I'll admit, I was very nervous ordering a second hand part from that far away, but as previously stated, buying it in the UK was just far too expensive.
I also ordered some of the 14mm 'Dowty' washers as recommended here, but given that a full set of washers was included in the purchase of the pipes (I knew the banjo bolts were included but not the washers), I ended up not using the 'dowty' washers. I definitely have other things I can use them for so they won't go to waste and are a great design. I was unaware that these existed until they were suggested.
I also took the advice on the silicone tape and purchased some "Permatex Self-fusing Silicone Tape". This stuff was great and I used it to wrap the new pipes on the exposed metal sections and over the rubber protector (where my original pipe eventually rusted through). The pipes are new thoroughly protected.
I drained the oil and removed the oil filter (It was also quite rusted so I changed it for a new one). The oil cooler pipes came OFF without incident and I took the opportunity to clear the whole area around the joints with engine degreaser. Refitting went without any problems and I torqued up the banjo bolts to the setting in the workshop manual.
Finally I refilled with oil and let her run for a while so I could check for leaks. Nothing so far and I think it's job done. I have left the belly plate off for now so I can easier inspect the area for a while.
Oh, I also applied ACF anti-corrosion grease (the blue stuff) to all the banjo bolt heads and any remaining exposed pipe so as to fend off any early corrosion.
I'll finish this with some photographic goodness.

