Here you go..I think I found one in your price bracket.. SG$750 with shipping..
https://www.amazon.com/Kardon-Chann...09-20&linkId=d336b3f8ee906829a6015f3584b5fd0e
But actually, I'd go with larger 5-6 inch driver speakers instead of the 3 inch found in satellites. 3 inch speakers cut off at around 100hz.. 5 inch can go to 75hz. This makes the low end more defined. So when there's gunshots and drums you can hear them coming from the speakers instead of the subwoofer only.
For me I got lucky on carousell.. Managed to get 5 focal sibs for $250, a Yamaha slim subwoofer (yst-fsw150) for $150 and for atmos 2 x Sony ss-sr35 for $30. So yes a 5.1.2 under $800 is possible but need good timing.. Usually Dec when ppl get bonus and upgrade
Focal sibs used for $250? Is this the one?
https://www.crutchfield.com/S-9eAD0TW32Ai/p_091SIB51B/Focal-Sib-5-1-Pack-Black.html