How to convert MIBs to snmpwalk output?

Hi,

I need to develop a monitoring module, but have no access to the actual device I need to develop for.
If I had the device's snmpwalk output - I could simulate the device (e.g., with snmposter) and start the development.

Is there a way to convert the device's MIBs (which I do have) to an snmpwalk output?

Any ideas would be welcome.
Ron.