Edit: If you've already done a Difficult rank or higher battlefield, or an AA battle on normal or higher, I would also say to get the Memises sword from Oboro.
If you must pick between sword or jerkin I'd go with jerkin. Sword is easily replaced with better option, but jerkin is still a decent acc swap for certain jobs.
Maybe within a month or two I will have the funds for another character, But until then I have one. I'll hold on my Plasm. My linkshell we are getting close to beating Tojil. Just a few more practice runs to get everything down packed