Here's a thought.....
I would seriously recommend getting a mod with a separate battery. It just gives you so much more choice and flexibility. You can charge most of them with the battery inside via USB anyway, but a charger and a few spare batteries gives you much more range.
A fairly small single removable 18650 mod will work well for you at 50-60W.
Then maybe pick up the new (and still hard to find) Hellvape Destiny RTA. It's a single coil rebuildable tank, so gives you the rebuildable thing you are after, plus a tank. And if you want more juice capacity, you could sit it on a small squonk mod like the Aegis Squonk. Best of all worlds!
Another one to look at would be the Oumier Wasp Nano RTA. Similar thing.....