Master cylinder ID

[X22SS]

I wanted to see if anyone had any ideas about what range out cars this might work on and what would be a fair value. I know it would be a core since it's old and been sitting on my shelf for 20 years. I'm pretty sure I took this off a 1968 Impala Station wagon with disc brakes. The casting number is 29881, there is a symbol that looks like GL5 at the front. I'm assuming 225 cast in a square is the date. Thanks, Mark