Is it worth rebuilding a broken front wheel
You would need to cost it out, as it pretty much comes down to the dollars cents.  

With a wheel at that price point its worth considering a rebuild, presuming you have a good wheel builder at your LBS. If you buy a new wheel, ensure the cost includes having the new wheel tuned up by the LBS. (If you not buying through a shop, add the cost having a shop tune it when it arrives). 

Unless the hub has low miles, consider a full service with new bearings, or at least put the cost of this into the rebuild of the wheel.  

In terms of if its worth it, you may decide reusing the hub rather than adding it to a landfill adds to the worth of a rebuild over a new wheel.