Whats wrong with this picture?

[K5Ken]

Ken, You don't need a bolt head, just the extractor, and they're easy to change out. Most times when a Mosin extractor breaks, it's really old, or it's on a refurbed rifle, and it wasn't fit finished. And that doesn't take much either, some fine grit wet/dry paper to take the sharp edges off.
Mosins are a "push feed", vs the "controlled feed" of a Mauser. That means the extractor has to push over the lip of the rimmed round. Look at the bottom of a Mosin round, the edge of the rim is beveled to assist in that process.
Make the area of the extractor that slides up and over on that bevel, nice and smooth. It will chamber a round better, and less stress on the extractor.
Give the chamber, lug recess, and extractor cut in the barrel a good cleaning too, the easier the case extracts, even less strain on the extractor.
If that's all Russian to you, or you're not sure about doing it, bring it by and I'll do it for you, take about 15-20 minutes.

My son already placed his order for the whole bolt head, would it be better to remove the extractor and put it on his original bolt head or just use the new one. Was wondering if there would be a head space issue.

[TRAP55]

We had seven or eight Mosins we checked the headspace on, all at the same time. They all checked out. Then we tried the bolts in several of the others and checked them, all were good.
That said, better safe than sorry.

[WeldonHunter]

We had seven or eight Mosins we checked the headspace on, all at the same time. They all checked out. Then we tried the bolts in several of the others and checked them, all were good.
That said, better safe than sorry.

Yep, this /\ I have 17 Mosins and they all passed headspace checks but I have had them fail when switching bolts/heads. Better safe than sorry. Depending how much you shoot you will need to recheck it periodically anyway and it beats paying a gunsmith. Takes about one minute.
Here's the set I have. http://www.okiegauges.com/sales.html At a minimum you'd need the field gauge but the no-go and field are good to have. Todds a good guy to deal with. I'll mention too that there's another brand being sold that look like these and they were copied from these. The quality is not the same. They are copies not made by the seller from what I've been told. Todd makes his himself.