how much does a ct20b turbo usually cost?

For just the turbo, how much does the ct20b usually cost? Thanks.

I've seen from $650 to $800

like $700

$500-$800

$650 here: http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&category=33742&item=2475627782&rd=1&ssPageName=WDVW