I don't know about original clay tablet on which this was written, but it can be found through the original publication I think: https://www.jstor.org/stable/1359157, if someone has access to JSTOR.
About the interpretation, I myself understand only the:
/igi nu-mu-un-du[8]/ - "I don't see anything"
The rest is a bit above my level. But check this alternative interpretation of this joke: https://twitter.com/abbyfheld/status/1501880993833054208