I will note that the figures Pevo quoted you for potions are retail value- he's assuming you'll trade them directly to the consumer (e.g make potion in exchange for healing/food/shelter on the road.) Revereorder is going to resell them, so he won't pay full market value- something you can/will negotiate with him for, however. No, I'm not pulling numbers out of my ass, I've got a handy dandy spreadsheet to refer to.
Anywho, something I've been meaning to do for a while but haven't gotten around to- talk about the map!
That map. Now, this map is basically
scribbled on a napkin, so don't expect perfect accuracy, but it's good enough to be getting on with. Since we're discussing travel, I figure'd I'd better throw out a rough scale and some travel times for your deliberation.
Thrimesdur- from river to river- is about 400 miles across, which is something like the width of Poland. To put it another way, traveling from one end to the other without any major interruptions would take you about 17 days on foot, 13 on a horse. Much like Poland, Thrimesdur is basically one big plain- rolling hills near the mountains, broad expanses of plains, and small, dense forests near rivers and the Black Swamps. From Yicelafo, it would be 300 miles (13 days) of walking to the Sacred Grove, barring poor weather, bandits, undead armies, so on and so forth.
The Jeweled Coast is something like 300 miles from end to end, although none of the cities' influence extends very far inland. Each city is rather unique, with its own system of government and resident population. It's only about 100 miles from Yicelafo to the nearest city, but since that journey is through thick, treacherous rainforest you're still looking at 6 solid days of travel on foot- sticking with the Caravan (and its associated carts and wagons) ups that estimate to 9 days, barring monsters, savage animals, hostile tribes of lizardfolk, severe weather, so on and so forth.
I think that covers everything that might factor into the immediate "east or west" decision facing You, so I leave you to it.