I'll have to add anther vote for Quality Light Metrics. The work is great, and the price was pretty reasonable, about $70-80/each for new cells and adjustment/calibration as I recall, some time in late 2007. There's no website for them, but the email address is
georgepmilton@worldnet.att.net. His English is very good, since he's been in California for decades, but if you talk to him on the phone he still has a strong eastern European accent. It took me, a farm boy from the deep south, a few minutes to figure out what he was saying.
I sent two Weston Master IIIs, and one came back with a 'new' non-bent calculator ring at no extra charge. The replacement calculator wheel was more than I had been counting on. I'm sure they are recycling the mechanical parts from old meters, since clearly Weston isn't making repair parts, but who cares so long as it comes back better than it left. The cells, I think, are brand new. I would *NOT* try to save the cost of the cell even it your cell seems to work; just buy a new one from them and get a known item instead of who knows what kind of shape your cell is in.
The calibration, BTW, was spot on. The two Weston meters I got serviced match my Soligor and the viewfinder meters in my Contax RTS and my 167MT to +/- 1/3 stop across the ranges. (Now I can carry a Weston and a folder loaded with EFKE or ADOX film and get shots just like the fifties!)
MB