help me design tubed version of the fet oscillator

They say a jfet is like a triode.
I want to design a triode version of this oscillator http://qrp.gr/regendetect/index.htm the source gate capacitor is formed by the internal capacitance of the fet, but I won't mind adding one in the tube circuit.
the tube will be the 12dw8 operating at an anode voltage of 12v.

Please give me hints where to start?