I highly suggest Jugner Forest for farming the sleepshrooms for these, in particular the area called Spore Hollow on the map, just run thru and link every Funguar in the area, kill them all, rest to full link them all kill them all, repeat repeat, etc. (63 THF/NIN) Also, yes you can easily steal sleepshrooms from them.
Water clusters are easy to get in Pashow Marshlands, and chamomile is sold for about 120 each from a little girl just to the left of the Ru'Lude Gardens auction house, down some steps.
Poison flour is in the far back of the gobbie shop in Lower Jeuno, sold by Pawkrix, about 515 each.
Thats 7620 gil for a stack's worth of materials, +2k for me for each stack of crystals, since I was lazy and didn't farm crystals. Thats about 10k a stack roughly, assuming you don't break a terrible number of them, and sleeping pots sell for 35k a stack on my server. Skill up and money? {Yes, please}
Just thought I'd share. After doing tons of holy water I was looking for something fairly easy and didn't notice this for a while.
Also, I didn't notice that skill ups were too bad myself, maybe you just crafted at a bad time for skill ups. (I've made nearly 5 stacks of sleeping pots successfully and have gotten around 2.5 skill ups in lvl I'd guess. That seems pretty normal to me.)