This should do it but might be a better way I didn't see.

SELECT

 x1.master,

 x1.type

FROM

 tblX x1

INNER JOIN

 (

  SELECT

   x2.master,

   x2.type t1,

   x3.type t2

  FROM

   tblX x2

  INNER JOIN

   tblX x3

  ON

   x2.master = x3.master

  WHERE

   x2.type = 'avail' and

   x3.type = 'oper'

) o1

ON

 x1.master = o1.master and

 x1.type in (o1.t1, o1.t2)