These are the 1537A 16 pin dip package used on earlier SSLs
that seem popular in Europe ,
Also used in and for Compressors [ not pin compatable with DBX type ]

Have spec sheet with experimenter notes & pcb layout for generic circuit as
well

i have only the higher grade ceramic ones now [ all the plastic ones are
gone now ]

7.00 each while they last !

thanks regards Greg , p.s. will consider trades for parts [ i need input
transformer siutable for
a.p.i. preamp ]