I have bought several second-hand Weston meters and they have not worked for long - they seem to be particularly fragile. At least compared to my Ikophot and Leningrad meters which I have had for several years now and both get regular use. And both are in agreement with my modern Canon 650D's internal meter so I can see no need to pay for calibration.
That's wierd, really wierd. I got a Master III sometime around 1985~ and liked it so much I bought another, new-in-box, as a spare. Well, I'm still using that first one, and it's still accurate. Wierd.