Looks complicated to build
Its not really. Simple 2 transistor push/pull oscillator built around a tv flyback to give ~20kV @~20kHz.
and needs an argon or helium supply.
Air works just fine. Probably even better for surface treating plastics - all those oxygen radicals do a great cleaning job.
Ideally you want to set this up for dielectric barrier discharge.
Years ago I built a low pressure version for treating LCP, and the increase in glue bond strength was incredible. LCP is one of those difficult plastics.