Did you take a look at Funding? The returns are lower but the terms are shorter as well. Most investments are around the 8% & 6 months duration. I never had an issue investing with them when I was using their platform, although a couple of loans extended for a month while the borrowers obtain new finance.
There's also La Trobe but their returns are variable on 'book' loans. https://www.latrobefinancial.com.au/ There 48 hr access at 5.15% is pretty good. Used them in the past, no issues.
Have you considered the likes of Plenti & Truepillars with their 'books' of loans? They're not mortgage backed but they do run provisions for any losses. Plenti loans notes are 9.0% (Jan-Mar 27 fixed term) & Truepillars 8.1% (3yr fixed term). Plus they do shorter periods for lower returns. https://www.truepillars.com/content/investors-home https://www.plenti.com.au/ I've currently got money in both. The first of the 3 year Truepillars matures in Sep, never missed a payment & last year they paid bonus interest in Jun (9.1% vs 8.1% p.a. just for the month)
