You can get an AFL booster seat for $51.75 and a Harness for $37.50.
The teams available are:
Hawthorn Hawks now sold out
Carlton Blues now sold out
Harness now sold out
Target haven't listed this in their listings but these types of booster seats are generally from age 4+, although I think it may also go on weight as well so this might now be suitable for children who aren't very heavy.
Shame there's no Port Power seats. My niece would love it (and by 'niece' I mean her parents)