As Warnie has said, to do this as indicated, you are going to need an Australian Financial Services License (AFSL) and an offer document, either an Information Memorandum (IM) or a Product Disclosure Statement (PDS). If you do not have these and promote such a product, you face the very real risk of fines and/or jail time. It's not that I have a problem with the concept per se (that's a whole different question), but the form. Be very, very, careful in how you plan this.