My understanding of Heuer during this time period is it was in disarray due to the quartz crisis. When demand for the divers took off, they were scrambling every which way trying to come up with part to fill orders - so there is a little less consistency in builds during this period. ie Some dials made in france, some swiss made, some no name at all, etc... here is one I picked up from Thomas Lubbock last year, although it's an auto.

http://www.heuerheritage.co.uk/heuer-diver/4540124661

I think I ended up paying 2000 GBP

: Hi All
: Firstly thanks to Heuerville [comment-reply@wordpress.com] for
: pointing me in the direction of the Heuer Forum.

: Any information on the rarity and value of my model 844 bought new
: in 1974/75 would be appreciated. Unfortunately I no longer have
: the receipt but I was 20 or 21 (63 now) at the time of purchase.
: I have had a new battery fitted and she is running fine and
: keeping time with my phones clock. Whilst the case was off I
: took a couple of pictures of the inside of the case and the
: jeweller identified the movement. The jeweller commented on the
: fact the old battery contained mercury which he stopped using
: around the year 2000 so it hasn't running for the last 15 or so
: years. I have been using his shop for many years, the battery
: came from him and it wasn't old stock, he distributes batteries
: to the jewellery trade so stock continually turns over.

: Model 844 quartz
: 42mm case
: Number on case 3648
: Brevet SA marked inside of case
: Movement Ebouche Swiss (ESA)
: Spelling on face "Professionel"
: 24 hour numerals in red
: Cathedral hour hand

: Any comments or questions to start off the discussions would be
: great. I have pictures to post, which is beyond my computing
: skills, hopefully my friend will upload them over the weekend.
: Thanks
: Graham