I have no knowledge of metallurgy so take this with a large pinch of salt, but I once read that ancient bronze (don't know how this differs from modern bronze) could look like brass. So for a bright bronze you could try brass.
I also happened to find, through painting a fantasy figure, that gold with a brown/red wash (Ogryn Flesh, I think) looked like quite a nice bright/polished bronze.
I am sue you will get some more educated answers than this.