I agree with Joseph that there probably isn't a better word for "literally" when used for its meaning:
In a literal manner or sense; exactly
(The first definition under Oxford Dictionaries–not to be confused with the Oxford English Dictionary–which is currently being scraped for Google's definition
of the word "literally".)
As a direct answer to your question, Joseph's suggestions may be your best bet:
actually, really, truly, factually, etc. with some reorganization
of the sentence to fit them in.
The premise you provide is that the use of the word "literally" as an emphatic replaces its use as "In a literal manner or sense". I agree with you that although this use has existed for a long time, it seems to have become more common. The use as an emphatic is now
common enough that some dictionaries have added it (like the second definition in Oxford Dictionaries: "Used for emphasis or to express strong feeling while not being literally true".)
However, other words like "totally" or "definitely" have experienced similar transitions in meaning and still enjoy use with their literal meanings. I would like to think that from context the reader should be able to decipher whether the word "literally" is used in a literal, emphatic, or ironic sense.
If you look at the examples given in Oxford Dictionaries for the first definition of the word literally, the meaning is quite clear from context:
- The driver took it literally when asked to go straight across the traffic circle.
- Darsana literally means view, in the sense of having a cognitive sight of something.
- One wonders if he knows where the bodies are buried, perhaps quite literally.
Though I can think of humorous cases where "literally" is attempted to be used in the emphatic sense:
- It's literally raining cats and dogs outside.
- You're literally killing me.
I cannot at the moment think of an example where you would use literally to mean "in a literal manner" and be misinterpreted for the emphatic sense. The closest I can think of is ambiguity out of context.
If we take your lunchtime example, the use of "literally" as an intensive in "I'm literally so hungry right now" is clear. In fact, the phrase is clear without context. If we substitute figurative language, "I'm literally starving right now", the meaning is unclear on its own, but again would regain clarity in the casual context of coworkers getting lunch. Although these uses might make you cringe and sometimes might sound silly, I don't think this means anyone has to worry about being misunderstood.