Well tbh the best and cheapest way to get this is to hunt down yagudos and trade there necklaces to the woman in windy. its about 220 necklaces but I did 250 to be safe.
I have to say that the Beads is the easier route. Just keep trade beads till you have Rice Ball Prices @ about 151 and you should be able to get the quest no problem
Another alternative is Shady Business. It's the same thing as Mihgo's Amigo but with Zinc Ores. Which can also be gotten in Giddeus. The only downside is they have a much lower drop rate but you only need around 100. I turned in 16 Ores and 160-ish Necklaces and that got me rank 4 fame.
Yag neck is definitely the easiest way to get this scroll. Just go out Giddeus with just a weapon and if you have it /thf. it takes a little while but the less trips the better. If you have the satchel now it will make this even easier.
I also suggest for new people to the game not to level this as a first job. Ninja is not a cheap job if done well. And if you get past 12 and don't have this spell you are pretty much useless in a party.
Ninja with out this spell is like a whm with out cure ^^
Started out with 168g per rice ball, traded 25 times with Zinc Ore, and traded 12 times with Yagudo Necklaces. Brought me down to 152g.
(100 Zinc Ore, 48 Yagudo Necklaces) Averaged about 2k per each, 296,000G.