Integrated with switchable voltage

Might take on an assignment oversea where they use 240V, but want to make sure I can still use it when I return. Is there one out there, prefers tube, that has voltage switching capability (without sending the unit back to manufacture)?

Not sure what speakers to partner the amp with yet, but most likely something small so amp should have at least 50 wpc.

Another option is to use step down transformer, but prefer not to go that route.
Nuforce Integrated accepts voltage from 100-240 (Automatic). The new Creek flagship, the Dynasty, has a voltage switch, but I don't think any other Creek amps do. I also believe the Linn Majiks have voltage switches on the bottom. I don't know of any tube or hybrids that have a switch though.
Just now is advertised an Aronov 930 tube interated for around 600. That is an integrated tube amplifier, which easy to convert back and forth. I could email you the datails how to do, if you interested.
Thanks for the suggestion so far. Nuforce definitely sounds like an interesting idea. Aronov is out of business, but can still be a good contender since tube equipments generally don't go bad. There are not too much info on Aronov, will have to do some research on that.

I wonder if Nuforce has enough power to drive medium sensitivity speakers that's typical for bookshelf speakers. Tube is still my preference...
I have heard both in my system. Nuforce has a more extended, more detailed but somehow colder (some call it neutral) soundprint with a leaner midrange. Aronov is just wonderful in midrange, and has the right treble, maybe the bass is a bit less differentiated. If you mostly hear classical music, as I do, there is no contest. Aronov is the better ticket, as far as my taste concerned. If you hear mostly rock, pop etc - maybe nuforce is the better solution, especially taking into account its size, energy comsumption, easy to travel with and no-fuss construction. Still, it is radiating out RF and, for example, deteriorates tuner reception audibly. I dont know what other implication it might have.
The Marantz PM-17 inegrated amp is switchable on my unit. Reference series at a solid and slightly warm 60 w/c. Out of production but can be found used. Later can be paired with two SM-17 amps which are bridgable to 200 w/c, using the PM-17 integrated as a pre-amp. Not tubed but warm.
I went the other way, buying in the US and importing to the UK. Conrad Johnson are switchable by changing the input connections on the transformer, from series to parallel I think. Spectral are switchable, in fact I know of someone importing a Spectral Pre and buying an expensive voltage transformer, only to discover a simple switch to change voltage, when he lifted the hood!
Most manufacturers make for a world market, it is only sound business to make them saleable in all markets, by easily adjusting input voltage. The exception may be valve amps. I imported a Viva Solista from the US and adapted the voltage. However, capacitors kept blowing and evidently, it needs new transformers as well, which is being done at the moment. That may appy to other valve(sorry tube) amps. Incidentally, I rather annoyed the designer of the Viva amps by importing from the US. I hope he has removed the Fatwa against me. Most manufacturers and importers hate grey imports and you have to factor in the loss of support you may have from the distributors in your own country, if you do bring a unit into the country.