Hi Mike - if pitching the fly and / or inner separately is what you're after than you don't need free standing necessarily. Have a look at the
Tarptent Notch and the Big Agnes Fly Creek UL1. Both tents pitch inner only and the Notch can pitch inner or outer only. The Big Agnes is close to free standing with the pole structure. I had mine on a river bank and it worked without pegging down.
As far as a comparison goes the Big Agnes doesn't need trekking poles but is slightly heavier. The Notch is lighter and has two usable vestibules compared to the Big Agnes' which is pretty small.
For a single wall shelter, any condensation will form on the fabric. I don't have big issues with it and just wipe down the wall in the mornings with a cloth if I need to.
Big Agnes would have a dealer in the UK so you should be able to buy locally and you might get lucky with TT stock here or otherwise just have it shipped to the UK.