I don't know what you would salvage this sort of motor from cheaply, but as a new product, NetGain has contracted with a motor manufacturer (SME) to provide a low-voltage (up to 130 V) AC PM motor and sells it (as a package with a controller) as the "HyPer9".
It is intended as a AC PM replacement for NetGain's Warp motors.
While I think that the typical "industrial" style of shaft of the HyPer9 is poorly suited to automotive applications (no auto engine has a plain shaft with a keyway), it is what everyone gets with their "forklift" motors and seems to be what you're looking for.
Previous threads in this forum about the HyPer9:
It is intended as a AC PM replacement for NetGain's Warp motors.
While I think that the typical "industrial" style of shaft of the HyPer9 is poorly suited to automotive applications (no auto engine has a plain shaft with a keyway), it is what everyone gets with their "forklift" motors and seems to be what you're looking for.
Previous threads in this forum about the HyPer9: