newbie here, where to get a deal on a impeller shaft for a sn92?

i am not opposed to used as i see new ones are pricy, the rest of the rebuild parts including races are needed also, just got this thing off ebay and found the shaft is badly pitted, the balls and races don't look too bad but i am not putting it back together like that so it can chew up the replacement shaft. i am planning on installing it on my bmw 325 so this should be fun, i hope to be able to search and find info without needing to resort to asking dumb questions that have been answered dozens of times

I bought a used shaft from Paradize wheels, it was about half the prize of a new one.