Just a word of caution about the old Weston meters - there's a reason they're cheap. It will vary widely from meter to meter, but many of them are using old selenium cells and they are no longer reliable. Any individual meter you may find may be in good working order, or it may be accurate only in relatively bright daylight, or it may be totally insensitive to light. The only way to determine that is to have the meter in your hands and test it. You can easily spend the price of a new electronic meter buying bad or inaccurate Weston meters trying to save a couple of dollars. Not to mention the wasted film. Four or five rolls of slide film and processing and presto, you've just paid for your meter!