The last batch I bought was from Topgun Aircraft - maybe Steve still has some R8s... I think what we really need is for a gloplug manufacturer to start making some specifically for turbines. I'm not sure what would drive the design - perhaps a longer body to get the element deeper into the combustion chamber. Perhaps having the element more exposed, and longer, would help, with the element thickness similar to the R8.

Time for the turbine builders to chime in...