I could only find these books online talkhis usool ash shashi atyab ul hawashi sharh usool ush shashi by liaqat ali rizwi some other dars e nizami books are also available at marfat and archive
It is good and simple Muzeel'ul ghawashi by maulana hakim najm'ud din ghani sahib e bahr'ul fasahat (1932) is an old good work
al-Tasheel al-Kaafi Fi Usool al-Shaashi by: Shaykh al-Hadith 'Allama Qadi Muhammad Ayyub Also Naadir al-Hawaashi by: Mufti Muhammad Akmal