Neo magnets are way to strong for an AFX/AW build. Dash made some a few years back but they are useless waaay too strong. They would require an all metal gear train as well as a rewound low ohm motor. Polymer are the way to go BSRT and others on eBay make them.
Can hop up magnets for the magna traction chassis be purchased anywhere ? I have only seen "neo" type and they are to powerfull for anything I would build.
Neo motor magnets do have a place, but it's in the low ohm armatures and high supply voltage world. I am running the Dash neos that sjracer mentioned in my two unlimited 4 gear dragsters at 26v. They work there. Also as Sjracers said, the poly motor magnets are the way to go, but they also need a little more voltage to give full benefit. They also need at least a mean green to get the benefit. They won't work well with a stock arm.
Steve for the mean green even Poly magnets might be to strong. I generally use a good set of stockers or Dash ceramics for the older AFX cars. If you find a set of Polys that read around 12-1400 I would try those, as they are only slightly stronger than a good set of stockers.