TP-Link WDM Ethernet Media Converter for $43 + free shipping
Buy via eBay offers the TP-Link WDM Ethernet Media Converter, model no. MC112CS, for $43.24 with free shipping. (Amazon charges the same.) That's the lowest total price we could find by $2, although we saw it for pennies less in September. It converts 100BASE-FX fiber to 100Base-TX copper media or vice versa.