A great, but somewhat rare and unknown, exposure meter is again available on ebay:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewI...em=200431668910This light meter has a variable angle of metering and functions as both a spot meter and an averaging meter.
It's a fine alternative to the Pentax and Minolta spot meters.
Also listed (go to "see other items" at the Bewi listing) are manual focus Mamiya 645 lenses: 35, 75, 105-210, and a 80 Biometar in Mamiya adapter.