I have been using a JTL LM8 Light Meter for last three years and am very satisfied with it's performance.
It has the range you are looking for.
Shutter speed range 30 min. to 1/8000 sec. (1/3 step)
Aperture range f1.4 to f90 in 1/10 stop increments
EV scale -6 to +25.9 in 0.1 increments
ISO range 3 to 8000
Regards
Ed