I have a small German tool the came with a step down transformer for USA market. The motor is very small so its not very big. I would check eBay and elsewhere to find out what a step-down transformer would cost to run the watts needed, which I would take the stated wattage and double it.

Or, if to expensive, find a moon lighting license electrician, and see what he would charge to run a 220v outlet to your darkroom. Unless you area is different, prices should reflect the market, meaning cheaper now than 2 years ago.

If it were me, I would run the line, however, I can do my own electric.