Midwest Gun Works has the ACR stock in stock and ready to ship, both black and coyote brown versions, $193.14.
I got the stocks in today for the ACR adapters, I only did one of them so far. I got the SP5K together for now... I watched the ACR modification video before I started. It wasn't too bad but I did opt for the can of beer version. It fit well and was solid and I can see thru the sights still. I think it would be more comfortable with an optic. I'll know better at the range but I added some photos so you can see how it looks so far.
When Negotiations Fail HK