For the longest time I looked for replacement rings and when I finally found one I liked it just didn't work for my game any more. After that I used an invisible wedding ring mod that hid both the engagement and wedding rings. I've been messing around SimPE for a while now and am beginning to learn a few things, such as that not everything has a texture file, some things are changed by changing the colour of the TMXT files.
I'm getting ahead of myself though. Hopefully the colour is okay as I was going for a lighter yellow colour but I didn't want white/silver rings. I also hope it works in your games as I don't have a way to test it outside of my game.
For the record I own all EP's and SP's except for Happy Holiday stuff and the rings appear in my game.
Let me know.