I don't think so - Israel would align with someone else at this point. They also are so small and they get a lot of support from Jews across the world. The situation is different by this point. I am sure they would severely feel it - but they are not going to pack their bags and leave like the South African white establishment did. There is a religious and cultural element at play and at this point there are enough rich and powerful people that would help them.
I still don't agree that it would be as simple as you're making it seem. After the recent back and forth with Iran, they were depleted of a majority of their supply, especially the missiles utilized by their iron dome/arrow defense systems which is the exact reason why they pushed for a ceasefire. (Side note: A whopping 14% of our very own THAAD missiles were drained in that exchange which is a staggering amount considering the time and cost it takes for us to produce those. This was an alarming exposal of our own military supply chain issues.) If it's not America or Germany, next up would be China or Russia. China has no incentive to provide such thing since doing so presents a threat to Iran who is one of their major oil suppliers. Considering China's long standing foreign policy of non-intervention, I don't see a reality where they would be inclined to be a primary supplier to a rogue state. Russia has a strategic relationship with Iran as well and providing weapons would create a conflict of interest on that front nor would they be keen on providing assistance to an ally of ours. They are nothing without us.
Plus if America decides to cut them off, all our puppets around the world like Turkey, Egypt and the EU states would fall in line.
Align with who? Nobody can provide what America currently provides to Israel - like a total immunity for any diplomatic, military or economic problem.
