If you do venture into the world of fountain pens and inks, justify the cost by declaring yourself an artist, and declaring your pens and inks to be art supplies.
Here is a drawing I made in my trusty 50¢ comp book*, of some rosemary, garlic, and carrots that we got at a farmer’s market:
Since most fountain pen ink is water-based, you can smear it with your fingers for a watercolor effect.
Bonus: your fingers will look artistic too.
Possible extra bonus: you can also call yourself an “ink-stained wretch.”
NOTES
* Composition books with paper made in Vietnam tend to be more fountain pen friendly.