Having had a dog with xrays similar to yours, I'm going to offer a perspective different than the "wait and see" approach. My surgeon whom I knew and trusted before I ever got my puppy (August 2009) suggested we replace the left, the worst of the two hips, as soon as it seemed the his growth plates were closed. He said if we did so, it was likely that the dog could live well with the right, the "less bad" hip the rest of his life.
Waiting until there is pain means waiting until there is substantial deterioration. If you have a stoic dog, you may not see pain until there are a LOT of degenerative changes, not just to the hip, but the spine, and the shoulders and elbows. Dogs with bad hips throw their weight forward and their front ends do a lot of the work.
I did the total hip replacement surgery in November of 2011. We did formal rehab for several months following that. After that, we put in a $500 above ground pool (with another $700 for a landing so he could get in and out easily). He swam almost daily March - October until this year.
The last couple of years, he required a pain management regimen that utilized lower doses of 5-6 drugs that approach pain in different ways. This was due to the right hip, not the hip we replaced. In hindsight, knowing what I know now, I think I would have replaced both, the one in 2011 and one in about 2013.
But with that replacement, he lived an active happy life, reaching almost 10 years before hemangiosarcoma took him.
If you can swing the cost, especially if you have insurance, I strongly suggest consulting another surgeon. Mostly, please know that waiting does have risks. Inevitable degenerative changes can't be undone.
Good luck to you. I know the feeling when you see the xrays. It's a punch in the gut. It's devastating, but we have options we didn't have even 20 years ago, and they're good options.