edmund, thanks much - I ended up calling customer support and these are the following codes that they "downloaded" to my remote:
code 1320 for the onkyo tx-sr501
code 1877 for the pace dc550
I haven't been able to check them yet so I hope they work. If they don't I've been trying to read up on creating wav files to program the remote from my comp. speakers (don't want to build/buy a jp1 cable if I can avoid it).

thanks much for the help!