The upgrade in the US is $79. If you want the standalone version, is available here:
Lightroom is near the bottom of the page. Indicate that you want to upgrade and choose the version that you have and the price will change.
In my opinion, the creative cloud plan is an excellent value. You get continuous Lightroom updates as well as the latest Photoshop. But it does cost $9.99/month. Only you can decide whether that is of interest to you.