Is this card available for purchase now?
Yes.
It is on the IC site. Does anyone know if it will still work with a stock 1000?
It's intended for machines with Zorro slots (A2000, A3000, A4000). In theory, if you had some sort of Zorro expansion out the sidecar, maybe? But I'd probably look to do an internal IDE solution before having all that stuff hang out the side of the machine. Assuming you're running KS 1.3 floppies, it would be a rather janky looking external drive if you got it to work. Be cool to hide one in an old metal external drive enclosure, though...
In theory it would work in a Phoenix model, but you wouldn't be able to close the case. Back in the day Jens made a Buddha Phoenix version, too, but those are probably as rare as unicorn horns these days (and not really applicable to your questions).