Help controlling an old component with a universal remote!

[phantompwr]

Ok, this might be a long shot, but I wanted to give my parents a nice universal remote as a gift. I am getting an RTI T1 remote, and I had my sister secretly write down the model numbers and inputs they are using because I live 6 hours from them. They are visiting in two weeks and I wanted to give it to them then.
My problem is with the receiver. It is an old one, a Sony STR-K502P. That model isn't on the list of codes that I have, and I can't learn their remote without tipping them off to what I'm doing, since they would have to ship it to me.
What I am hoping is, that one of you might know (or suspect) of other Sony receivers that use the same IR codes, and I might have one of those on my list. Of course, if one of you happened to have the RTI codes for that receiver then that would be a miracle... just throwing it out there.

Thanks in advance to anyone that can offer me any help on this!