Brendan, there's an online nursery in Lismore, NSW, that offers cola nuts for sale. You'd have to pay postage (Aust Post going rate) + handling charge ($4 for the first plant) but, more importantly, I don't know if the nuts being sold are viable for germination or whether they've been dried/fumigated/processed in some way. (I suspect that they're not for growing because they're offered in the retail section, not in the nursery section of the website.) Anyway, it might be worthwhile dropping them an email (the website link is shown below).

I've never dealt with this nursery so know nothing else about it.

Of course, exchanging some fresh nuts/seedlings with a GardenWeb member would be the much better option ... if you can find someone who has them.

Here is a link that might be useful: Medicine garden

I'm interested in some beach almond seeds. Emailing you privately.