Does a Warlock really learn spells from scribing them? I don't play Warlocks, but I was always under the impression that the power is granted by your patron. Unless you're talking about a ritual, with your feat, which, yeah, you learn.
Spell Scrolls are 25gp for Level 1 and 75gp for Level 2, but I would add that I think only "common" spells (IE ones that have been in D&D for a long time and are well known) would be readily available. And NONE of them are available in Julkoun. Still, a month is time enough to travel, so you could go to Daggerford, or quite frankly Waterdeep, to go shopping.
I'm not really doing Downtime by the book. For both Downtime, and Overland Travel, I've been doing a simple Skill-check thing, where I just get everyone to come up with a skill (or two or three) and an intention for it, and a roll, and I adjudicate it based on that. I've got some mental guidelines, but mostly it's based on intent, and bad rolls can give us unintended consequences, but not necessarily failure.
You sound like you should roll Arcana as one of your rolls, at least.
If you want to pit-fight, I just re-read some of the early stuff for this game, and it looks like Morwen refereed your first batch, so I doubt that she'd be against you doing some in Julkoun to get the crow's spirits up. It's up to you, though.