It was seeing the gorgeous pictures in your book that made me redouble my efforts to find one of these for myself :) I didn't see any for a long time, then two in the space of a month, both effectively NOS. Missed out on the first but grabbed the second - which someone else tried to buy hours after I'd made payment, so getting your hands on these is pretty hard, I'd agree.

The 150 number comes from a PDF Tag-Heuer produced in 2004, when they were celebrating the Carrera's 40th birthday - it's a really nice document with some great shots of TH-owned examples of all sorts of Carreras. Unfortunately, I just had a look around my PC for the original PDF but couldn't find it - I have a feeling it must be either on an old PC or HDD, but I do have a print of it.

The relevant text runs (my italics, Tag-Heuer's bold):

"The worldwide success of this timepiece (the previous paragraph was about the Chronomatic/1153) prompted the creation of a number of limited series gold timepieces (total of 150 timepieces) launched in the 1970s. They coincided with the partnership between Heuer and the Scuderia Ferrari )from 1971 to 1979) and every Ferrari driver during that period received one of these chronographs:

- Carlos Reutemann (1977 & 1978)
- Clay Regazzoni (1970 to 1972, then 1974 to 1976)
- Jacky Ickx (1971 to 1973)
- Niki Lauda (1976 to 1976)
- Mario Andretti (1971 & 1972)
- Gilles Villeneuve (1977 to 1979)
- Jody Scheckter (1978 & 1979)

Drivers of other teams who were ambassadors of the brand also received chronographs:

- Jo Siffert (1971 on BRM)
- Ronnie Peterson (1971 & 1972 on STP March)
- Emerson Fittipaldi (1974 on McLaren)
- Dennis Hulmes (sic) (1974 on McLaren)
- John Surtees (1974 on Pace-Mass)

Demonstrating a timeless bond to motor sports, these automatic versions of the Carrera chronograph were all fitted with a tachometer on the flange of the dial as well as a 1/5th of a second scale outside the dial."

I know we've usually taken production numbers as either guesses or with a pinch of salt, but as these were more or less made to order, I think a production run of 150 sounds entirely feasible.

I'll try again to find the PDF, it's a very nice document for us to have archived somewhere. Or maybe someone else managed to find it and store it somewhere? At a pinch, I guess I could scan my printed copy.