(present circumstances notwithstanding) I'm not sure, long-term, any Iranian government would have any more reason to trust Russia's than any other "Great Power's" offer to provide such an essential service.
Who would France trust? Who would Britain? (Ok, Ok, don't answer that last).

Edit: A
truly international authority, organisation and undertaking would be a different story.
The present Iranian government, I would have thought, must be planning more nuclear power stations, as you say (is there really no record of that?), assuming the long-term strategy of providing itself with a long-term independent energy source coupled with conservation of petrochemical industry raw material reserves (which will almost inevitably become much more valuable in the future) is their real aim.
As regards military options, since that's what
we say the fuss is about, of course it would have been much better if nobody had started threatening anybody in this way in the region in the first place... But, come on, we all know which of us carry the really big sticks around here (and there). The issue there, it seems to me, is that we're saying, well, neither the US nor the Soviet Union were MAD enough to step over that line (although, in the US's case, history tells...); however, when it comes to Islamic governments (in our ignorance or deliberate denial, perhaps) we suspect insanity.
Meanwhile, of course, Western Powers and their corporate interests have in no way, on their side, ever threatened nor been seen to employ aggressive covert nor overt means, as opposed to normal diplomatic and commercial means, in order to grab natural resources out of the lands of others. Oh, wait.
I don't know. Convince me. I just don't see the credible threat from 'their' side. I do see much threatening behaviour (and accompanying propaganda) on 'our' side.

We are all aware of the alignment of powerful interests, and of their history, on 'our' side.