I'd probably do something in sterling silver like Lois Hill or Tiffany's. Your budget won't go too far or bring you something too substantial since gold is up so high these days. Good luck and have fun shopping for a RHR!
Or, what about a simple diamond band? I also like gemstone rings- like a sapphire solitaire w/ diamonds on the side or band rings w/ gemstones. I have a zillion other ideas, but am not really sure your taste in jewelry. Just throwing some things out there!