Yeah it's possible..
From memory the Garmin 400 does it... so does the Universal UNS 1C
So there should be plenty others that should do waypoints from known navaids..
However two rules when using GPS...
Rule 1/ Check the coordinates of the reference waypoint your using against the chart. Pay special attention to the N or S and the W or E.
Rule2/ Re-read Rule 1.
