not easy to find as even before Delta closed down the pen was already discontinued, however I consider the Delta Parthenope Old Napoli as a very nice example of what you are looking for.
The pen is designed so that the shape, size and balance is best when the cap is screwed on at the end.
The Parthenope (on the right) was also available in red marbled, brown marbled and blue marbled, besides black.
Look good will try to see if i can find further info and a price- Thanks
This Taccia Covenant Midnight Breeze has a screw-on cap, exactly the size of the barrel, that screws softly onto the body. Very satisfying to undo but gives the pen a bonkers balance if posted.
Whilst it ticks one box for you, I'm pretty sure this unticks another.
Lovely pen and for some reason produces some of my finest handwriting.
Wow, thats looks like it will be a tall pen. don't recognize the brand- where are they from?