Re: Define 'local'
"It is not clear to me about whether or not the hydrogen and oxygen used to make the water was from outlying molecules of the planetary forming disc or if they drifted in from unrelated stellar space.
If local then the water of life would still vary from system to system. If not local the clouds should be visible in interstellar space rather than just around forming systems"."
I am assuming you mean just Hydrogen and Oxygen molecules - otherwise you would think Oort type objects. I think it is reasonable to think that material is merging from outside our system, but I would wonder if it just collects in the outer reaches until it falls inward with one of the objects. I was looking at this chart for perspective:
At the same time though, in the early formation of the sun and the solar system we were still in the cloud where other stars were born. You could look at it as if gas was arriving from outside the system, or we were all part of the same system. You could surmise that any gases outside our system falling in are really from the same original system. (I know The Reg had this article but I was having trouble finding it - fell free to sub the link)