You are not likely to notice the difference between Nikon and Pentax lenses for the most common primes.

The only times I've needed a shutter speed of more than 1/1000 is either shooting really fast action or trying to shoot at wide apertures on a bright day and/or with faster film. If you have ISO 400 speed film in the camera and its a sunny day, you can only really choose 500@f/16 or 1000@f/11 (add a stop if your film has the latitude). Even 100 speed film only gets you down to f/5.6@1/1000th.