I have a number of these. I have been picking them up off eBay for about the last 10 years. You can get them for 10-20% retail if you are patient although prices are increasing a little lately. I only have the cheaper models but have 3 or 4 mechanical ones. Have about 15 in total. My favourite is a quartz yacht timer.
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I am here:
http://maps.google.com/maps?ll=54.276831,-0.413855