My experience was with die casting a long time ago. That process would not work for this part!
Depending on what your needs are I would imagine that you could do a sand casting with a core. The core would be comples and probably fragile for such a smal part. The core molds would also be complex. There would be alot of work going into this before you even had a part.
Consider a lost wax process also which might be a bit easier.
A hard mold would be very complex if this is a low production rate item. It might be useful to consider though.