[Amps] Alpha 76A; Variant ? Industrial Transformer

[Patrick Barthelow]

Another discovery on my "mystery" Alpha  76A.  It is suspected by one or more of the brain trust here, that the transformer was possibly taken from Alpha Industrial inventory,  MRI related units.   The transformer is open frame, with no "bells" but transformer paper and tape, covering the outside of the windings, and the power leads in/out entering top and bottom, both sides.
Clues:  I have not weighed it, but in moving from old QTH to new QTH by car, it was REALLY heavy.  Opening  the cabinet shows the old style stacked laminations 7.5" wide, 6.25 high, and 3-1/2" thick.  The other clue is near zero clearance, left edge of xfmr core with the control board.  Looks like only one set of holes, (same ones used) studs for transformer chassis mount.  It looks like it  overfills (very tight clearances) the designed space for the transformer for the amp.  The Core stack is Stamped  BTC 11163  and appears to have date stamps 83 35,  Any ideas on the nature of this particular transformer?  
73,
Best Regards,   
Pat Barthelow    AA6EG