This is not a Black Friday deal specifically, but they make a batch and sell them out:
https://www.midwayusa.com/product/1020904239
I bought two of them and they are pretty cool for building up a simple lightweight upper. They have a dowel pin that positively locates the handguard in relation to the upper, not exactly monolithic, but sorta. I moved my 300BO 7.7" pistol over into one of the 7" versions. I had a 10" carbine upper I sold to a buddy but before I did I shot it a fair amount and it seems great.