Not my field at all, but these are very common at the shows here I think, the next Militaria do is Malvern at the back end of Nov and the Shirrell Heath LRDG usually go mob-handed. I'll happily pick them up.

Regrettably I had some excellent ones and more, from the late Maj.H.M. but I donated them all to the now defunct REME Museum at Arborfield. As it happens now, it would have been far more meaningful to have donated these to this worthy cause.

Possibly more common your end, but I'll look/ask if you wish.

R.