Yes, you can indeed do mistlands pretty much as soon as you can make a karve. Dangerous as all get-out, but possible, and you'd probably need to build and use a block trainer beforehand which requires going swamping and sailing for enough iron and serpent scales for a stonecutter and lvl 1 serpent scale shield. Then you "just" need to sail around in your karve till you can find at least 5 cores-worth of dungeons outside of the mist, if you can and at least one dverger-occupied base. Technically for just krom and the arbalest you dont strictly need the dverger base but since you're already in the area anyway and will likely find several before you find a dungeon...