Elixirs of healing should be differentiable according to how channel energy scales; i.e.:
Elixir of healing 1d6 (CL 1)
Elixir of healing 2d6 (CL 3)
Elixir of healing 3d6 (CL 5)
...
Elixir of healing 10d6 (CL 19)
If we apply the similar item cost concept (similar potency equals similar cost), we may price the basic CL 1 elixir of healing as slightly cheaper than a Cure Light Wounds potion of minimum caster level (1d6 vs. 1d8+1 hp), and then extrapolate from there, bearing in mind that the average hp increase of the Cure Wounds spell progression rises faster relative to the average hp of Channel Energy levels.
Elixir of healing 1d6 (avg 3.5 hp) ~ Cure Lgt. Wounds (50 gp, avg 5.5 hp)
Elixir of healing 2d6 (avg 7.0 hp)
Elixir of healing 3d6 (avg 10.5 hp) ~ Cure Mod. Wounds (300 gp, avg 12.0 hp)
Elixir of healing 4d6 (avg 14.0 hp)
Elixir of healing 5d6 (avg 17.5 hp) ~ Cure Ser. Wounds (750 gp, avg 18.5 hp)
Elixir of healing 6d6 (avg 21.0 hp)
Elixir of healing 7d6 (avg 24.5 hp) ~ hypothetical 4th level potion (1,400 gp, avg 25.0 hp)
Elixir of healing 8d6 (avg 28.0 hp)
Elixir of healing 9d6 (avg 31.5 hp) ~ hypothetical 5th level potion (2,250 gp, avg 31.5 hp)
Elixir of healing 10d6 (avg 35.0 hp) ~ hypothetical 6th level potion (3,300 gp, avg 38 hp)
Condensing, we get:
Elixir of healing 3d6 (avg 10.5 hp) ~ 300 gp ~ Cure Mod. Wounds (300 gp, avg 12.0 hp)
Elixir of healing 5d6 (avg 17.5 hp) ~ 750 gp ~ Cure Ser. Wounds (750 gp, avg 18.5 hp)
Elixir of healing 7d6 (avg 24.5 hp) ~ 1,400 gp ~ hypothetical 4th level potion (1,400 gp, avg 25.0 hp)
Elixir of healing 9d6 (avg 31.5 hp) ~ 2,250 gp ~ hypothetical 5th level potion (2,250 gp, avg 31.5 hp)
From which we can derive the progression (
#dice + 1) *
#dice * 25 gp, or:
1d6: 25 * 2 * 1 = 50 gp
2d6: 25 * 3 * 2 = 150 gp
3d6: 25 * 4 * 3 = 300 gp
4d6: 25 * 5 * 4 = 500 gp
5d6: 25 * 6 * 5 = 750 gp
6d6: 25 * 7 * 6 = 1,050 gp
7d6: 25 * 8 * 7 = 1,400 gp
8d6: 25 * 9 * 8 = 1,800 gp
9d6: 25 * 10 * 9 = 2,250 gp
10d6: 25 * 11 * 10 = 2,750 gp.