Re: Accompany old piano
Does the piano have sentimental value? If not, you should get rid of it. The piano, theoretically, can be tuned up to 440Hz, but it is a prolonged process - much more than tuning up a piano that has been at 440. Also, if the piano strings are old, you could have an issue with tensioning up all the strings (breakage). Depends on when it was dropped to 430.
As far as dropping the tuning on your sax, you could try gutting out a mouthpiece to make the chamber larger, but there's no guarantee of how the intonation will fare.
Have you tried pulling the neck out of the body some? That will get you a few cents, though maybe not consistently through the whole range of the horn.