I would just collect ripe fruit straight off the tree. Use a free draining seed raising mix (eg. 2:1, fine sand:peat). Softly rub fruit to puncture and flatten then place on the seed raising mix in a seed tray and cover with a very thin layer (<0.5 cm) of the mix. Keep mix damp and in a shaded location as this species prefers these conditions. As it is winter you may not get much happening for a while. Be careful not to ruffle up the mix too much as this will disturb the germinating seeds. I'm not sure of the germination rates for this species, but you should get at the very least a few to grow.
Cheers, Rowan