I too have a Taurus .38 Spl a duplicate of that of Mikeful with the exception that his appears to have an adjustable rear site which mine does not.
Perusal of Taurus's web site is enlightening but doesn't answer the question concerning when this pistol was made.
If it may be of any help, my pistol was purchased new in box Dec1976 in Miami, FL from a gun shop there. The SN on mine is 8123xx. I don't know anything about how the assigned serial numbers might relate to manufacture date but I would think that the serial numbers would go from low to high with the lowest numbers being manufactured earlier. Thus you gun was made earlier than mine I would think. As for where these guns were made, I would think that they were manufactured at probably the original Forjas Taurus plant in Porto Alegre, Brazil as indicated by the roll marks on the gun barrel. The info on the Taurus company web site seems(at least to me) to indicate that the Porto Alegre plant was their sole plant until they bought lock, stock and barrel in 1980, the Beretta plant in Sao Paulo, Brazil. The Miami company(INT. DIST. INC) being their USA importer.
Just as a matter of interest, over the years I have shot countless numbers of rounds through my pistol never with any problem and consider this pistol, like all Taurus weapons, to be outstanding and among the best made. The vast amount of shooting in my revolver was with reloads which I put together using bullets that I cast primarily from earlier clip-on wheel weights. No doubt they were considerably warmer(but safe) rounds than the store bought variety. I also own two other Taurus weapons, one being the model PT 99, 9 mm auto and it too is as good as they come.
Just my thoughts on this matter which may or may not be in the ball park.