https://www.jetpens.com/Delfonics-Carrying-Bag-M-A5-Dark-Denim/pd/37102

Delfonics Carrying Bag - M (A5) - Dark Denim<br /> $36.00

Perhaps a bit large, but could be used as a mini-portable office to hold a variety of things including 4 x 6" index cards for work on the go.

https://www.jetpens.com/Retro-51-Tornado-Classic-Lacquers-Rollerball-Pen-0.7-mm-Stainless-Body/pd/8233/refills

JetPens has a pretty comprehensive list of Parker style refills that will work with the Retro 51 Tornados, including ballpoints and a variety of nib sizes from broad to fine.