Arc welders and Variacs


I saw an ad in the paper for a new Lincoln arc welder for $199.  It appears
to be one of the smaller "home-type" jobs that probably has a duty cycle 
of about 5% or less.  My question is will this be sufficient for tesla coil
work (regulating a pole pig), or should I hold out looking for a used welder
with a much higher duty rating?

The next question is, does any one have a variac that they could sell me?
I am looking for 0-120 volt ~10 amp (~1.0kva) for controlling things like 
rotary gap motors.