It's really, really hard for someone to recommend a lens to someone else -- we have no idea what you like. We can do a bang-up job at recommending the lens we'd use, but that may be completely meaningless to you.
The obvious question, though, is that if you have two lenses, why don't you take them both? There's a reason why lenses can be changed -- and why most of us have more than one of them!
That said -- sure, the 135mm would be a good lens to use! So would the 210mm. Good luck on your trip!