I have to agree w/TJLazer about the availability or rarity of NTSC A600's here in the states compared to A1000's, but I don't think your proposal is way out of line. If I didn't already have 2 A1000's, and had more than one A600, I would consider the trade, but then my only A600 is not 100% as it has an intermittent keyboard problem.
You may find someone that either has two A600's and is willing to make the trade, or only has one and would rather have the A1000 for nostalgic reasons in their collection.
It is really quite funny that so many Amiga users have become Amiga collectors (like me with 18 Amigas) and desire to have one or more of every model produced.
I would like to trade one or more of my Amigas for a clean, working A3000T, not that I need one for any reason, but just to have a more complete collection, and because I think that the A3000T was one of, if not THE best Amiga models every produced.