Pre-64 and post-64 carrier springs are very different.
Try Winchester Bobs; http://winchesterbob.com/
, and Brownells; http://www.brownells.com/
, for your spring. Brownells pre-64 stuff is not in the factory parts section, they are else where.
The carrier springs will take a set. When you take a 94 apart, don't take the carrier spring out unless it's broken or worn, or you replace the carrier. In my experiance they won't work properly when you put them back together.
Since the carrier spring has made a bur on the carrier, I'd suggest replacing it. It may be less expensive and easier than haveing it repaired. There are several variations of carriers even in the Pre-64's so make sure you oder by serial number.
The plug screws don't need loctite.
Don't have the cartridge stop on the link brazed, have it welded with steel weld. It will last longer.
The magazine follower should be just forward of flush with the inside wall of the reciever when correct, and the cartridge stop should be about 1/16th of an inch away from it. Just pointed enough to stop the case from reaching the carrier.
I can't do you a pic without tearing mine apart or I would. Like I said above, there should not be an under the carrier jam, no matter how slow or fast you cycle the action on a Mdl 94. There is only ONE thing that controls the feeding of the cartridges from the magazine and that's the cartridge stop on the front of the link.