I dont know the name of the shop,but that street that has city market,as you approach from the I&M building direction toward city Market,stay on the right side,there is a shop you will see selling curios and have displayed some of those coins on their display,they buy ( those East African coins with a whole in the middle) i think they also buy the bronze ten cents/five cents coins. Just check other curio shops in that area also.
Niône mwisho ya mwezi pliz!
Meru Holiness