Using UK 230v in US

I’ve purchased a Naim Atom Unity to use as a DAC into an Octave integrated amp.  Wrinkle is I purchased a Uk model because they are considerably less expensive.  There is no switch to change between 110 and 220v and I don’t really want to mess with sending to the factory for conversion.  So I will be using a step up transformer to move my 110v up to 220v.

Any recommendations on a transformer for this and any other concerns that people would flag?  Given I’m using it to feed into an amp I’m not thinking there is much fidelity risk around the power supply to the naim given I’m just using it to convert the digital to audio. Thanks!
I looked at the internal pics.

IF it's like I think it is, then almost any tech could do this for you, in about 15 minutes.

If you don't wanna go the way Erik mentioned, then just buy a "quality" made not one of those cheap ones on ebay etc.
A DAC,if I'm not mistaken, would have a steady current as oppsed to amps that have instantaneous pick currents which are higher than the stated wattage... 
So if your DAC's wattage is say 30 watts then in reality all you need is a 30 watt transformer, but get one in the 100-200w range so if you buy another item like a cd player etc. then you'd be able to use this transformer for those things too.
check this company out, their 100-200w transformers are less than a hundred bucks.

Really appreciate the advice.  Thanks guys.