Path stored in TStream?

Is the filepath of a stream stored in a variable anywhere in the TStream itself?

I looked through the source code and couldn't find it, but didn't have the time to look very thoroughly so may have missed something.

Not every stream is open from a file (it may be a network stream by example), so even though I didn't checked I'd bet the answer to your question is no. Look in the derived type for file streams.