I agree with all the folks that say conversion from 50hz 220vac to 60hz 120vac with an external transformer is AOK.
Here is a link to a 500va auto transformer. The only thing you will probably have to change or get an adapter for is the output connector.
http://www.digikey.com/product-detail/e ... ND/4915272
I also agree with the folks telling you that you will be carrying some extra weight along with you. In this case an extra 11 lbs.