Hello Donny,
Provenance in private collections reaching back 70 years is certainly rare - really no info surviving for this keris?
One more pertinent thread:
http://www.vikingsword.com/vb/showthread.php?t=11767
BTW, I'd also believe the blade to be from Madura. However, I just recently burned my hands, so better wait for confirmation by folks with deeper knowledge in things Jawa/Java/Madura...
Regards,
Kai