I am so sorry
I can't really comment on the shoulder xrays, but I will say I have seen worse hips than those in the xrays.
This could definitely be a costly venture, and honestly, only you can decide
While I know I'd be thinking with my heart vs my head or pocketbook, I'd probably do one leg at time
But again, that can be so unrealistic in this day and age.
I wish we were all millionaires and cost was never an issue when it came to our animals.
such a very hard decision for you..and so unfair