Hi Garg ji and Gehlot ji,
I have seen a few trees of
Xylia xylocarpa
along roadsides near Karnala Bird Sanctuary.
Adenanthera pavonina is found in some popular gardens. Veer Mata Jijabai Bhosale Udyan, Mumbai has this tree listed.
In either case, I think fallen seeds need to be collected. I am not aware where they are sold.
Regards.
Dinesh