Online emulator http://demo.opera-mini.net/public/ works - so it is independent on browser java plugin - as microemulator doesnt work, as browser use outdated java plugin, and as it is said on Oracle java check - Mozilla 52 versions on - does not use java plugins.
@williamearle18 You don't say what platform but there are old versions going back to 5.0 for Android at: http://ftp.opera.com/ftp/pub/opera/android/mini/
If you poke around in ftp.opera.com you might find something for other platforms. Otherwise Google is your friend as always.
Keep in mind that old versions night not work well or at all do to server side changes.