The Sidewinder SCT 3800kv combo is being replaced by a new combo. But as far as I can tell only thing that is changing is the motor (and maybe the decals). It's still a 1410 3800kv but it's sensored. Sensored motors can be ran sensored or unsensored. So you should be ok. As far as supply, even castle's website shows them out of stock. So maybe they have to catch up on demand.
as of me typing this, Amain has them in stock.