All Onkyo and Integra receivers use the same IR code-set. If Harmony do not have the Audyssey codes set up for your particular model try using a different one. Which Onkyo do you have?
Here are the codes in Pronto CCF format for a lot of different receivers:
http://www.awe-europe.com/ir_232.html
If you download the spreadsheet for your model you can see which codes it is capable of responding to.