240/350 hubs have the seal set into the hub shell. Is this what you don’t see?
Seal wouldn’t serve as a mechanical limited to how far the freehub body can slide on. However, if this hub was serviced prior to sale and had a new driveside bearing, it could be that the shim ring wasn’t put back in. You can tell if this is missing as if you look into the hub drive side with the stars and spring removed, the shim should partially hide the bearing seals. if you see all of the bearing seal, there’s no shim. Shim sits under the drive ring. Its late though and I cant figure if this would cause spacing issues.
Other things could be that the star ratchet spacer (slides onto the axle) is mushroomed having been over tightened, allowing over compression of the hub when assembled and binding.
I’ve had a hub where I’ve thrown in a cheap bearing. before installation the bearing is fine. Installed its notchy and stiff, after removal its fine again. Presumably tolerance issue and squashing the outer race too far. perhaps the bearings are doing this once side loaded.