Best place is the Jaulian Monastry. Before you start your climb on the stairs, there are numerous cold drink/refreshment shops below. Ask them you want replicas.
What to buy: Replicas of various statues and murals are available. As I have already warned you in the tourist trap, it is illegal to purchase originals.
But if you still eally really want to purchase, Shops below Jaulian Monastry is the best location. However do not be fooled, they are replicas. The vendor will be selling you stating these are real, but they are good copy. They will ask for thousands of Rs., buit settle for hundred (at least 75% discount). Tell them you will check at the Museum. Maybe that will scare him, as they are not allowed to sell such items, even replicas.
(will post pictures of replica bought by us later)
What to pay: Rs. 100 to 600 max
Shops are lined up on the Taxila road.
What to buy: Taxila is famous for making mortar and pistle, and is renowned all over Pakistan. They are cheap in Taxila compared to prices for this at other places in Pakistan. Being a tourist they will charge you and arm and a leg. Negotiate.
They are quite heavy, made from local rocks. And maybe a bit difficult to carry on the airplane. They weigh from 3kg to 10 kg, depending on the size you want.
What to pay: Starting Rs. 250 and up, depending on the size.