Belles 150a : any competition at 1k level?

The 150a is a good amp but is not for some. It is not the last word in dynamics nor is it in transparency. You don't want to pair it with a warm balanced system. BTW-the Hotrod version is much better which is standard for this amp now. However, it does deliver a sonically sweet and smooth presentation.
At this price, I would look at some of the older McCormacks like the DNA .5 or the newer DNA 125. Both of these are available used in this price area and are excellent choices. Very clean and dynamic.
I have never heard the Stratus, so that is for someone else to comment on.
Also, Anthem makes a pretty decent multichannel amp that you could get in stereo configuration. Of course there's the Parasounds(Halo) and the like.
I give my nod to McCormack but that's just me.

Heard the Stratos at last Spring's Stereophile Show in NYC. Even at its full retail price (a bargain), multiple listeners, including myself, were very favorably impressed. Because any final choice is system dependent, there is a 30 day money back guarantee, which I gather from our demo is rarely invoked by purchasers. And, I think there is a twenty year (!!!) warranty.
Incidentally, the Odyssey loudspeaker line seemed to be over-achieving, too.