Yashica Mat 124 B

It's an unusual model in the Yashica range.

As you correctly say, The B is for 'Brasil' and the CdS meter is absent, so it's a cut-down 124G which shares most of the other components (and serial number sequence) with the 124G. It was made between 1981 and late 1982/early 1983 and by all accounts, the numbers built were in the hundreds rather than thousands. The lenses were standard Yashinon 80mm f2.8/Yashinon 80mm f3.5 as far as I recall.