I went to a place at Broadway today to ask them.
www.broadstitches.com.au
They quoted me approximately $20 for 50 plain polos (we can even mix colours) with pocket sized embroidery. Multiple colours of embroidery is not a problem. A greater purchase should result in a greater discount. Tehy do caps and stuff too.
They had heaps and heaps of t-shirts and polos to chhose from.
There is an $88 setup fee for the logo, it takes a week to digitalise it for some reason.
For less that $22 bucks each thats pretty good deal.