Where did you read this? Onkyo has used the same codes for over 10 years. It would be strange for them to change now, especially with this particular low end model. What universal remote are you using that isn't working?
In any case, the codes are in the harmony database. And Onkyo codes are in most every other universal remote.
This thread at RemoteCentral (and another one by the same knowledgeable poster) says he wasn't able to get the NR414 to accept normal Onkyo signals. Then in this thread, started probably by the same poster, Onkyo support says the codes are different. On the other hand, urcsupport.com says Audio 1805 "should" work with the NR 414, and UEI should know because they provide the IR data for Onkyo remotes.
We have seen that the HTX series of Onkyo receivers, and I believe also some Integras, use a different remote ID, which use the same device (210) and function numbers but different subdevice numbers. See this thread and the thread linked in it. I think that the user of these components could just change to ID1, but perhaps the HTX series doesn't allow that. The NR414 does allow setting the remote ID.
I don't know whether the standard codes will work or not. If they do, then lots of remotes will work. Of course a JP1 remote with cable will work either way, and I suppose that a Harmony should also work.