The freight fowarder in SA has contacted me about my crate. They want me to wire them the shipping cost. Is this how this is done normaly. The cost is not out of line but I am not sure about sending the money?

What I did was a wire transfer. Find a local bank that does them. You need all the info from the company. You need the bank info, swift code
branch info and so on.It should be safe with your bank.

Your customs broker can have them ship the freight collect and wire the money for you.