I have a full set of IR codes for the Onkyo TX-SR800 in my PCF available for download here.

The IR codes in question will be found under the device, "Pronto Signals (Onkyo TX-SR800 / RF / ID1)". If you end up copying the whole device over make sure to set the RF tab under device properties accordingly based on your brother's setup. I also have nice front and back images of the receiver under my device gallery so you know. Not sure whether you have a use for them or not, but they are there if you do. :-)