In the Language note (546 field),  LC does not use subfield-b to indicate the script a language is  written  in  if  it's  the  normal script  for  that language-- i.e., if  the work  is  in Ladino in Hebrew script, LC wouldn't spell this out explicitly.  If the script is Roman, LC would indicate this:  In Ladino$b(Roman).; if both:   In Ladino$b(Roman and Hebrew). Similar examples can  be found  in  RI 1.7B2.  NOTE the punctuation with parentheses (not semi-colon).
 
As  for Rashi script:  it's not  LC practice to note its  use  at all, since it's  a  *font* or typeface rather than  an individual
script and  is not considered appropriate for a 546 subfield-b.