you can use 1300nm LX gbics on 62.5 micron fiber to get a distance of 1804 ft (550 m)

http://networking.smsu.edu/general/info/CiscoGBIC.htm

LX Gbics are more expensive, but probably the solution to the problem.
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80gig red mk2 -- 080000125
(No, I don't actually hate Alan Cox)