I have no affiliation with this, just thought how rare this must be if it's really what it claims to be:

https://www.ebay.com/itm/392687882466?ul_noapp=true

I’ve seen that picture before. It looks like cobbled together 914 and 911 parts

The transmission is the REAL deal. It was a cobbled together by Porsche, using a 911 (905) transmission with a 914 tail cone. .

For 12K you would think they could put a clean tail cone on it. Looks like it is straight from the junkyard.

this transmission number is NOT from a 914-6 Sportomatic
the 914-6 Sporto used the 914/05 transmission with numbers like 7610001
my Sporto had the tranny number 7610027

Not sure looks like the real deal to me,who really knows ,AA have a car with one of these,sure there will be a response soon.
Theres a bunch of other parts (working) to make this system operate and that is the issue as they would be rather hard to find.