A picture or more graphic explanation would help a lot. For many double-handle faucets handles can be bought separately (especially on a secondary market).
A wild guess, that this may help:
https://www.ebay.com/sch/i.html?_nkw...cement&_sop=12
BTW is it a single-handle faucet? What exactly is broken (a handle itself is broken in half, a fixture problem, a valve malfunction etc.)? If you need just any handle for a double-handle faucet, then you can source a handle from [any public bathroom - not advised] a flee market or DIY it
from anything.