I know this is an old thread, but I think my answer will help someone who is currently researching. I have been in Hyderabad for over 5 years and have tried Avakkai mango pickle in few stores near my home. All of them good, however, my favourite place is Vellanki Foods in Madhura Nagar. Their pickles are delicious, spicy and tasty. It seems like they have an online store - Buy Andhra Avakaya Pickle Online | Vellanki Foods