the last time i went, all no have liao.
heard got those shopowners ask ppl go there collect, then they make
into jars and sell. 
TS can also try st. andrew's cathedral or blair rd. there are also
such trees at ang mo kio town gardens west behind the
soon-to-be-opened 24hr macs, but its a slope with ants so wear
shoes.
i saw the saga seed trees at alexandra hospital as well, but dunno
why on the ground dun have seeds. 