If you go to Norg and find yourself a little short of fame for Utsusemi, try to do all the other ninja scroll quests in norg first. I'm pretty sure some of the others have lower fame requirements, and can possibly bring your fame up enough to unlock the others.
This is what I did when I noticed my fame was slightly short. And yes, the rice ball price idea is garbage. The prices vary based on sales or such. When raising my fame they were 160-something first check, 156 second, and 160-something again third time (when I well and truely had enough fame). Doing all the other ninja scroll quests and the samurai job quest are good ways to help with your fame requirement too. I've seen lots of people that wasted tons of gil buying excess ore/necklaces to get the fame they needed before even bothering with the other quests.
It was something like 109 ores + samurai quest + some of the scroll quests in Norg to get the fame needed for utsusemi. Suggested numbers of ore trades were never consistent cause half the people would skip the samurai and other quests and use only ore, so their suggested figures were exagerated. There were probably miners/farmers exagerating the figures to increase demand/prices to make extra gil from sales too.