There’s a place in Manzini, Swaziland which sells them. I don’t remember because I bought my one in 2005 but I could find it again. It’s one of the local independent sport shops. But i realise that’s not very helpful!
Aro, I have a couple of spare Swazi shirts that I was planning on putting on ebay. One is going up today and the rest on the weekend. Feel free to drop me an email if you want one before I put them up for sale. firstname.lastname@example.org