You're certainly not the first to suffer this way, Mr Gazza. Is this the part 19540021A:
I think others on here have fashioned replacements using biro refills or aerosol tubes (5mm long if memory serves).
If you wanted to order one or more from Moto Rapido, I'd be happy to pick them up and post them to you as I don't think MR will post things below a certain value.