Oh, silly! The Russians will peddle the reactor parts to the Iranians, then sell any needed targeting or intelligence info on it to the US or Israel. Then, after the bombing raid that leaves the Iranian reactor as so much smoking rubble, they'll sell their good customers new replacements. Then repeat as necessary, or until the Iranians finally catch on.
The Russians are not fools, and have been fighting the common enemies in Afghanistan and Chechnya to know where their bread is buttered. And they're not getting their food from Iran....
-archy-/-