Speedy 105.012-65 of (68?)

Hi everyone, newbie here

Couple of weeks ago I bought 105.012-65 from a friend of my father that was showing some of his collection.
History goes that he bought this watch about 30 years ago from a local jewellery store, and for the last 10ish years it has been closed in the watchbox.
Upon inspecting it I found that the movement has a serial 260XXXXX.
So I asked him if at some point he changed or replaced the movement, and he said that since he bought it he just serviced it and nothing else.
So I wonder, since the 105.012-65 was in production until 68, is it possible that this movement is original to the watch?
With the extract from archives “closed” I can only rely on your knowledge

Thank you so much in advance for all the inputs

The dial looks indeed like a 145.012, which appears to be jet black.

Serial seems late for a 105.012...

Also, the top left lug shows a mark that looks like the Salazar stamp. Are you in Portugal ?

Thank you for your response.
Indeed I am, my father’s friend bought it in the 90’s on a jewellery store (2nd hand) downtown Lisbon

Yeah all of you are most certainly right….I’m the only one still hoping for the improbable, that this was one of the last 105.012-65 out from the factory in 68.
Indeed this is a B3. Spaced T dial, but from what I’ve researched this dial was also fitted on later 105.012-65. Even the case is the later more thinner one and without the “S” one the case back.
Anyways if there was a movement swap it must have been done before the 90’s, before he bought it from the jewellery store.
The case back as a watchmakers mark on it from 76 and if something was done it was back then.
From what I’ve heard the extract from the archives won’t be back anytime soon…so the doubt lingers on