Step up transformer

[sphelps]

The LEDs will run off dc power so the transformer you have converts ac to dc. I've never seen such a transformer that doesn't work for both 120 and 220 vac. So chances are you can just plug in the one you have into 120 but maybe need a plug adapter which can be purchased locally from places like London Drugs for around $20, cheaper on eBay.

You won't get an actual voltage convetor for $15-$20. $50 would be a good deal for something like that, but again unlikely it's needed.