Okay, found mine:
1. Fantasy Printshop FP808 : 1/72nd scale 36 inch and 30 inch Ps.
These are about 11mm and 9mm respectively. They are a rich "gold" yellow, and have two different fonts: one is thin with a semi-circular "loop" to the P, the other is thicker and has a square-with-radiused-corners style. There are 4 x 36" (two in each font) and 6 x 30" (four in "circle" font, two in "square" font)
2. Pavla 1/72nd Gloster G.40 sheet.
These are leftovers from my Gloster Goblin build. There are two 36" Ps, marginally smaller than the FP ones, and in a much lighter lemon-yellow colour. The font is like the FP "Square" font but the proportions are different, with the "loop" being more of a rectangle than a square.
You're more than welcome to a pair of any of them.