Looking for a summer mac - can you help?

[Thornham]

I'm looking for a single breasted summer mac - preferably without a belt. Something like this:

www.marksandspencer.com/Pure-Cotton-Single-Breasted-Poplin/dp/B004OGXW6U?ie=UTF8&ref=sr_1_29&nodeId=43109030&sr=1-29&qid=1303208890

would be great, except that I want it to be cream, blue, grey or green. Size 20 ish, which rules out some shops. Any ideas?

Is this Banana Republic one any good?

Goes up to a UK 20.

I've tried this on in store and it's lovely. Sadly, no longer doing the £99 special offer they were doing in March.

(it has a belt though, sorry!)

That's really lovely, but double-breasted doesn't really work on me. I am hoping for something fairly classic, though, which that one certainly is.

this jigsaw one

or

this mint velvet one

I tried both on yesterday and they are lovely - much nice in flesh btw!!