The pictures help. Assuming the gear leg didn't get bent and there is no damage to the engine mount, this should be relatively easy to repair.
You'll need to raise the nose wheel off the ground to get access and to remove the nose wheel yoke.
The "brass foot" mentioned is actually a plated steel part. As blaplante pointed to above, it is a "Lip Skid" from AntiSplatAero (not a Van's designed part). From their website, there looks to be a bolt or screw that holds it to the gear leg from the bottom....kind of guessing on this. This part has to come off first.
Next, remove the large nut from the gear leg along with the two bellville (spring) washers and the nose gear yoke itself.
At that point you should be able to remove the bolt holding the damaged WD-631, and the WD-631 itself. i have to agree with Joel...it looks like the part may have been installed backwards.
With the nose wheel yoke off, the remains of the sheared off cap screw needs to come out. You might have to find someone who has done this before and has the tools required. Hint: you don't want to mess up the screw hole in the yoke while removing the sheared end......kind of an pricey oops, and the yoke should be repairable.
Assuming no other damage, reassembly is the reverse...using a new WD-631 of course. Make SURE it is oriented as shown on Drawing C1, and SB 14-12-22. Also, replace the previously sheared off cap screw in the yoke. As for reinstalling the "Lip Skid", I'll leave that one to you. I do not have one installed on mine.