Hello,
the speaker cabinet that you have is a 412SR. It's original speakers are 4 12" Sunn Acoustic suspension transducers. It weighs 75lbs. and has an 8ohm impedance. It's power handling is 160 watts RMS. As far as years go it's hard to tell. You could try looking inside the speaker cabinet for a date, but it was probably made in the late sixties or early seventies. Hope that helps!
wil.