Signetics also offered a clone of the Intel 3001 and 3002, as well as
a control store sequencer unit, the 8X02.
I don't know if I'd consider the 181 a "bit slice". There were also
CMOS versions of this: SCL4581, MC15481, HCL40181, etc. And Moto
had the MC9704 mW RTL 4-bit adder (though that's probably really
stretching the case).
Cheers,
Chuck