One wedding/engagement ring?

Here\’s a question someone asked about art deco engagement rings:
Everyone in my family has a six prong Tiffany setting engagement ring and a plain band wedding ring. My fiance and I want to look for something that is antique,preferably Edwardian or Art deco. I love filigree and things that are simply interesting. I think it will be difficult to find a matching band. Do you think it is okay to just have one ring? Finding the perfect ring is like finding a needle in a haystack. My mom wants him to go out and buy a ring now, but I told her, round diamonds and Tiffany settings are aren’t a dime a dozen, but we are not running out of stock, so we are going to look.

What do you think, Engagement and wedding ring or just one ring?