The books library of Dawat-e-Islami contains many booklets of different writers including Ahmed Raza khan Barelvi books.
Why don't you contact Raza Foundation? Brother Riaz from www.razanw.org is very helpful. Al Dawlah published by Mufti Abdul Qayyum Hazarvi (alayhi rahmah) is a very good edition.
Does anyone know of a good bookstore in Karachi where these can be bought? (arabic books of Ala Hazrat)
isn't al-dawlah originally in Arabic? I think that has taqaridh too from scholars like imam nab'hani so could be good for your imam.
wa alaykum salam, Al-Amnu wal-'ula. Try and get the translation of Hazrat Taj al-Shari'ah. I have seen them gifted to Arabic speaking Ulama. The book was acknowledged and received with great respect and delight once they read it.
Assalaamualaikum Can someone kindly provide a suggestion for an arabic book by ala hazrat that can be given as a gift to a non-urdu speaking imam? Also what publisher would you recommend? Thanks