Australian Visa for US Citizen with 23-year old conviction

As you know the US laws make a lot of sense.

I was convicted for sex with a minor when two weeks after I turned SEVENTEEN years old; the 'victim' was my little boyfriend who at the time was 13 years old and about to turn 14. We had known each other for 2 years, but his parents freaked out when they found out their Christian son was having gay sex.

I never served jail time; I only did probation for 10 years. However, I had to register as a sex offender because gay relationships didn't qualify for Romeo & Juliet exceptions (aka minors having sex). It wasn't until recently the laws changed in my State, and the judge ordered my removal from the sex offender list given my age.

Based on your knowledge, what is Australia's policy when it comes to situations like this? What kind of visa, if any, could I qualify for?

Thank you