Good one Karl. How come you couldn't find the code letter decals ?
That said, I think some of mine are from 'Tally Ho', and no longer either in production, or available, although I think I saw some on e-bay recently.
Let me know what letters, and sizes, you need for both, and I'll see if I have some spare. I've got the 8 inch black serial decals, and two sizes of Dull Red code letters.