Old post, but you logged in several days ago, and you've been chasing this topic more recently on other threads,...but...you haven't been cross referencing those posts.
Well you've got the name of the town right elsewhere, but you've got it wrong here, it's not Villa Carlos Plaz, it's Villa Carlos Paz.
Salta 360 is the street name and house number, and Ty Bryn is obviously the house name, Sierra De Cordoba, is the name of the Province, possibly an alternative local name, the official name is Cordoba Province, and the country, which you already know, but didn't mention, is Argentina.
So his February 1983 address was...
"Ty Bryn" Salta 360, Villa Carlos Paz, Sierra De Cordoba, Argentina
Don't automatically assume that he passed around that time, it might be that your father was the only family member with whom he usually stayed in contact, so unless you know otherwise, stay flexible with the possible date of his passing, he might have passed much later than 1983.
You also know that his wife was called Irene, her date of birth was 8th July 1907, and she was still alive up to march 1960, you might know whether or not she predeceased your paternal uncle.
By 1960 your paternal uncle was a retired engineer, and given his age in 1983 chances are that the 1983 address was his last residential address.
Be super careful when you mention his name, and especially so with any record applications.
His name was David William (forenames) Powell John (surname) and his date of birth was 5th February 1902,...so bear in mind, and say so if you apply for any records, that his surname might be listed as either Powell John, or as John.
O.K. there are two cemeteries on the outskirts of that town, and if he has a grave chances are that it's in one of those, as might be his wife if she passed in the same area, which she might not have of course. There are also two more cemeteries several miles outside of the town.
There is address and contact information available for all those cemeteries, but leave that for now.
You're super lucky in regard to Argentinian death certificates, because my understanding is that they also contain burial information.
So, what you want is a acta de defunción = death certificate and in Argentina those are readily available to the public and they're inexpensive.
You can get that from the local Dirección del Registro Civil = the Municipal District Civil Registration Office.
I suggest that you write or email to the gentleman below, and I'm sure that he or one of his staff will be able to check the records for you and explain the application procedure to you.
I suggest that you write both in English and in Spanish, and if you need a Spanish translation, you can probably get that on a forum such as this one... http://www.english-spanish-translator.org/
Director de Registro Civil
Dr. Juan Carlos Zoppetti
Dirección: Sede Registro Civil – Alem esq. José Hernández - Ciudad de Villa Carlos Paz, Córdoba, Argentina - C.P.: 5152
Teléfonos: +54 03541 433443 / 436444
Civil Registration Director
Dr. Juan Carlos Zoppetti
Address: Headquarters Civil Registry - Alem esq. Jose Hernandez - City of Villa Carlos Paz, Cordoba, Argentina - CP: 5152
Phone: +54 03541 433443/436444
The abbreviation esq. = esquina con = corner (with), so esq. is the abbreviation of esquina.
Alem = Leandro Nicéforo Alem = a local street name
Jose Hernandez is the name of an adjoining street.
CP = Código Postal = Post Code