Help me find and locate this steering column part please!

[blkcorvair]

I need some wisdom. Seems I took my 69 3 spd column aprt to clean and paint, inspect and lube everything. I took alot of pics, but somehow I missed this small part. It has like a concave rubber seal that sits under it as well. I just cant remember where it goes?

Also notice that it is cracked in the picture. Does anyone know how to identify or where I can get this piece quickly. (i'd like to put this back together before I forget something else.)