The Melles Griot model 05-PSAA-905-065 will operate most 8 to 14 inch long HeNe tubes.
These are new units and have European standard wire color code.

Specifications:

Input Voltage: 115 / 230 VAC ±10%, 50 to 400 Hz.
Output Voltage: 1850 to 2450 VDC.
Output Current:  5.5 to 7 mA, preset at 6.5 mA.
Trigger Voltage: >10 KV
Input Leads: 4.5 inches, 22 AWG. Flying.
Output Leads: Flying, 10 inches cathode lead with tube clip, 5 inches anode lead with slide-on  ballast resistor (80K Ohm).
Dimensions: 6.0 x 1.5 x 1.2 inches (154 x 39 x 31 mm)
Mounting holes: 2.3 inch center spacing.

Features:

4 second Turn-on delay (defeat by cutting violet wire loop)
Output current adjustable with onboard trimpot.
RoHS compliant.