Photos showing more construction details would have been nice, but it looks to be a New Wonder alto.  These horns can be made to play well, but there is little value to altos and tenors unless they are gold or silver plated.  Definitely worth less than $400, and likely to be less than $200.  Also, not a big market for this model. 

That is a pretty ancient horn.

There have been too many advances in saxophones develpment and millions made since then, so it has little value.

The case looks pretty stable.

Is there a mouthpiece with it?

I didn't look before I started typing.

Sometimes they are worth much more than the horn.

250 is a push on its value.

Good Luck