Well, I've got the answer, but you're not going to like it....
YES, you can add a wideband to your car! The problem is that there is more to it than just adding a sensor and making a couple wiring changes. You also need a controller.
The least expensive option I know of would be one of the gauges by
ProSport. Including gauge you're looking around $220. This is only if you're only looking for a gauge, not programmable and I don't believe it has additional outputs which you'll want if you end up adding a system that can integrate with a wideband such as the MAFT Pro.
Now, since you've already got the gauge you could get the
LC-1 by Innovate Motorsports for $199. Look around and you may be able to find it on sale. The LC-1 is a popular and reliable unit, I own one myself. You may add an aftermarket gauge or Innovate's gauge for an additional price.