These older watercolour pieces of mine are available as posters and art prints on Printler! They ship to all countries in the European Union, as well as Norway, Switzerland, UK, and USA.
For sketchbook doodles like this I’m mostly using gel pens. My current favorites are Gelly Roll Moonlight pens on this Sakura 9x14 cm sketchbook. I also sometimes get various off-brand gel pen sets in neon colors (basically whatever is on sale at my local supermarket) so Gelly Rolls are not the only ones that I use for my sketchbook work. (: