what's the highest capacity 14500 cell?

Batteries and Chargers Rechargeable Batteries
67

A bit thicker than Nitecore NL-147 (diameter 14.2 mm) NL-147
Keeppower 14.6 mm, Keeppower

Summary of HKJ’s tested li-ion 14500

Yes, that’s nice price for Keeppower 14500 (with shipping).