According to the markings and the Paul B Anders tutorial, this is the real deal for a 73 2.0L
http://members.rennlist.com/pbanders/DJetParts.htm#parts
Bosch Part number is on bottom of ECU
3 numbers share that part
CU13X or the 022 906 021 E (Bosch 0 280 000 037)
$300 plus $15 for USPS Shipping - Firm.
Paid the same amount in 2011 to our NW peep on here with the initials RD!
I even cleaned it up to make it go in Orangina if she needed it, but it ended up a spare in the garage.
John
310-991-2200