Theodora doesn't start with the same sound as Tripoli.
I don't think that Tripoli is that outrageous myself, but if you want to think of names that sound like it you should pick names that start with Tr-. Such as
Trista, Tristana,
Trina, Triona,
Trixie, Trilby, Treva,
Tryphena,
Tryphosa, Tressa, or Trega.
Tivoli is a similar sounding place name that I've seen given to girls several times.