Price check on

if i put a 20/19 and a +29hp on the white scythe and fellblade tell me prices on those? and the sundering 10/10 bow is now 20/19

Putting mods on an item doesn't inherently change the price. As for PCs, not sure about the axes or Fellblade (might be able to get something because it is req 8). As for Shadow bow, salvage for Zealous string. You may be able to get 10-15k for the Sundering Bow.You can find the PC for the Ob Shard at the Rare Material Trader.

I'd get a second or even third opinion on the bows.

Fellblade - merchant food

Composite - 10k~

Shadow Bow - salvage for zealous

White Scythe - while somewhat rare to get 15^50 max dmg, imho 13^50 is too far away from valuable. Merchant food/Keep to yourself.

Chaos 8k~