It's a Godspeed turbo.. So Ebay...
Everything else looks alright. if you put a quality wastegate and a quality turbo on it, you'd be set.
But realistically, it's cheaper new.
91 318is - M50NV (gone)
02 WRB Subaru WRX EJ207 forged, 320 AWHP stock turbo.
85 - 325
02 325i Sedan