I'm happy to organise getting the tees and printing them once a design is finalised.
I'm sure my boss won't have an issue doing these at pure cost. Logisticaly it's a bit of an issue as we are all over Austrlaia and there is freight involved which until we are ready to send it is an unknown amount. That needs to be factored in either individually or as a total job lot. Understand that being in Sydney the Sydney teams wouldn't be affected by freight.
Things to keep in mind for the design are as follows;
How many positions for the print (each position means another setup and print cost)
How many colours in the print (each colour involves a setup fee)
Colour for the tee (white is cheapest, colours cost a bit more)
Style of tee (do we use a plain old cotton tee or something with a bit of contrast colour or do we go for a cooldry material)
For the cockroach tees we did a black tee with a white print just on the front. Simple

Maybe we can work it out that I ship each states tees to a central person or shop and then the individuals from the teams are responsible for picking them up or arranging postage etc. That's how I did it with the cockroach tees we did over here.
Sizes shouldn't be an issue, I can cater for kids as young/small as size 3 and go all the way up to moo moo size 5XL. I think this size comes with tube battens to stop the flapping when going upwind

Hardie and Nebs feel free to pm me if you want any other info or if you want to handle it totally differently.