Other option - 847. Caveat - Since you intend to put motherboard in it, don't get the JBOD variant (45 bay). The regular one comes with 36 bays and compatible with EE-ATX.
If you don't get any offers here, checkout Digitalmind2000 / PC Server & Parts has been auctioning off 847 with "A" type backplane one a week. Take looks at the recent sales, and contact them to see if they can offer a discount. They also have their own website. Couple of other reputed sellers - Tamsolutions; unixplus(they have other seller accounts); and pdneiman / The Server Store (they also have multiple seller accounts).