PL 100 should deliver ISO 100 in most developers, somewhat more in classic "acutance" developers like Beutler's and FX-2. Either of those two would be my first choise for this film. If I were to need even more contrast (for POP or salt prints?), I would bleach and redevelop in plain pyro/soda (1 liter water, 2 teaspoons pyro, 2 teaspoons sodium hydroxide).