My question is, where to find them. I have scoured the internet and lost a few ebay auctions. The only place I have found them was Southern Cross Militaria in Australia. The had what seemed like boxes of them, but they will not sell to me living in the States. Does anyone have a way to source larger bolt heads or have a treasure trove of them?

Or are there any other fixes? Weld on the rear of the lugs, file to the needed dimension, then re-harden the lugs? I don’t want to condemn the rifle to be a wall hanger quite yet!!!

I would appreciate any help from you very experienced people!!!

Just a tip. you may want to measure your bolt head from rear shoulder where it butts up against the bolt body, to the breech face.

Many numbered bolt heads have been rep-ground to something other than the "official" length. Don't forget that JUST length isn't the whole story. Bolt head "clocking", equal locking lug engagement, & firing pin protrusion also need to be correct.

Secondly find out WHY the excessive length is there. It could indicate a serious problem, or maybe just the wrong bolt head, but its worth a little detective work.

I measured my size 1 bolt heads and got 0.630”. Also I bought a new old stock bolt body and It helped a little but that was prior to my initial post

What could cause it?/ how would I check? Rear lug slots in the receiver?

It's possible the action body bolt lug recess surfaces have worn.  If they are kept clean and lightly greased, headspace should not change even after 10,000 rounds.  

It's also possible that this bolt required a #3 bolt head when it was built, but no way of knowing that now, someone could have swapped it out to get a #3 bolt head for another rifle.      

0.630" is certainly in the range of a #1 bolt head.  But, if your rifle currently headspaces at around 0.080", a #3 bolt head "should" bring headspace down to pass the Field gage (IIRC, a #3 bolt head will typically fall within 0.635 - 0.640).  The one #3 bolt head I have measures 0.636.  

Try the new bolt body and check again.  

Tape will compress easily on the gage giving you a false measurement, try using a feeler gage.  You may need to sacrifice a few feeler gages by cutting them into small pieces to fit between the bolt head and hs gage. I've used shim stock before too.  But, you really should get it to pass on a 0.074 field gage if your going to shoot the rifle.   

What he said ^^^^, don't go grinding or welding in that crucial area!

If your original bolts serial number matches the receiver  number I'd stick with it as it was hand fitted to that exact receiver. Now you just need to fin a bolt head that clocks & gives you the correct headspace as is, then sort out the firing pin protrusion & locking lug engagements AFTER you've determined what the real actual problem that is, or whether the old girl needs to retire.