Power Load Balance Concern

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "by way of Terry Fritz <twftesla-at-qwest-dot-net>" <Mddeming-at-aol-dot-com>

Hi All! 
        I am in the process of upgrading my power supply to 4 15/60 NSTs and
already have a 120v input -at-30Amp,  model W30M Variac. Based on nameplate
ratings, the NST bank  should draw about 33 Amps total (4X8.25). The problem:
since there is only one open slot left in my breaker box, I would like to use a
40Amp breaker, but I have not seen single breakers for this kind of current.
Most are dual breakers -at- 240 V using both sides of the line to keep the load
balanced and prevent in-house brown-outs.  If I try to get a 4KVA
step-down/isolation transformer so as to utilize both sides of the line, I am
looking at ~$350 plus S&H on 120 lbs. 
Questions: 
1. Is running the Variac at +10% a real concern? 
2. Is placing this size load on one side of the panel going to create in-house
imbalance problems? 
3. Anyone got a cheap step-down 4KVA transformer? 

Would appreciate response from any/all with experience in this area. 

Matt D. 
G3-1185