Modbus to ethernet converter

I have a single flow-meter with a modbus option card
I wanted to just use a single point modbus to ethernet
converter as all of the other meters are Ethernet
Can I use just a RS485 Serial to Ethernet converter
and still write code in the PLC to access the data or does it need to be a single point Modbus to Ethernet Type adapter
Anyone have a module they use for this

We use the Grid Connect NET485-MB.
Manufactured by Lantronix.
http://gridconnect.com/industrial-protocols/modbus/modbus-rs485.html

The EDW100 operates as a ModBus gateway.

http://www.eternity-sales.com/Westermo/media_converters.htm

Disclosure - ESI is an authorized distributor for Westermo.

I've had excellent luck with these:http://www.automationdirect.com/adc/Shopping/Catalog/Communications/Serial/Serial_Isolators_-a-_Converters/MB-GATEWAY

The InHand IG601 can be a modbus to ethernet converter.
http://inhandnetworks.com/intelligent-gateway.html