Firstly apologies for the rather blunt answer from a contributor below.
Lets give him the benefit of the doubt and say he was in a hurry to reply & that english was not his first language so his reply may come across a bit rough.

Now down to your watch.
I am sorry to tell you that the name Heuer was added to the dial at some stage and the watch was probably an unbranded watch originally. Heuer did not make a model along the lines of the one you have with that combination of components ( ie. handset, movement, dial style, case ).
It does however remind me of the style of a brand called Chronogaphe Suisse. These were produced from the mid 50's to early 60's very much in the style of your watch. I beleive your watch has a Landeron 148 movement, very robust & commonly in use from that era.
You can try googling images of Chronographe Suisse 18k and you will see many watches similar in style to yours.
As for value, well the false Heuer added to the dial does sadly reduce the value of the watch but the good news is there are plenty of extra untampered dials avalable through ebay etc if you wanted to correct your example. If you are merely planning to sell the watch then it would be best to be honest about the name Heuer being added at some point.
Good luck with your watch - Darren

: Hello,

: I am new here. We have few vintage wristwatches after my
: grandfather. I have found that on this forum are many experts of
: Heuer. I kindly ask you to help and identify what's the model
: and it's value please. Many thanks in advance.

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