Well, it seems to me you answered your own question. I had thought coal prices could fluctuate too, for example, but I assume not so wildly. Aren't we really talking about two things:
1. World supply of energy vs. domestic supply. Yes, there are different uses for different energy sources, but high oil prices will mean a push for more than alternative sources (i.e. mass transit may start looking more attractive to cities that don't have it).
2. Ending our "dependence upon foreign oil" for reasons that go beyond just the price we pay at the pump.
Should we build many new nuke facilities and then the price of oil were to drop dramatically, we might in hindsight attack the decision on nukes as a "waste of money." Should the price of oil stay high and continue to climb then I think it's reasonable to assume we'd be grateful for the alternate source.
But, given the concerns implied by the second point above, I think we should be willing to "eat the cost" of possibly bringing on "too many" nuke plants too soon. My understanding is that they are quite resistant to obsolescence. Given that it would inevitably be a big business/big government operation it can only be wished that some smart people would be exploring the possibilities of whether modern technology and design could help us develop "turn key" nuke facilities. Perhaps that is a pipe dream, but it would be nice if we could over-build during the construction phase, but save big on ongoing costs by not bringing certain portions of facilities online until they were needed.
Anyway, don't mean to be ducking your question. I don't know the answer as to specific costs of nuclear energy and wonder how much of it can be variable based upon the costs of essential materials used in the process. I do know that I can look around the world and see that many nations made the decision decades ago to go with nuclear, so I can only assume it is a rational energy supply.
I also seem to remember reading several times now that the founder of green peace has become a vocal advocate of nuclear power. I think I started reading some responses to him that were of the personal attack kind (in the pocket of "big nukes"), but his words come across to me as if they were written by a fellow who had done the research, had the resume to substantiate his devotion to the planet, and came to heartfelt conclusions.
There's also this e=mc2 thing. I mean from a layman's perspective I thought we were talking a somewhat high rate of efficiency. ;-)