Not a lot of options. AW or purple Efests. There are the red Efests, but they won't perform acceptably in a mech (to me) after a couple dozen charge cycles. I'm not talking about clouds. I'm talking about a noticeable lack of oomph - more like a gentle simmering than proper vapor production.
You can, in theory, go somewhat lower than 0.8 ohms with a recent 18350. However, you'll soon notice it's even more important with such a limited battery to
optimize it's output, not
maximize it.
I usually
vape my gennies at around 0.8 with 18350s in mechs all day long. Sometimes 18500s for home use. Hardly ever 18650s.