What tools are needed, just a press, any sort or removal tool? e.g.
You will need an over-axle bearing press. Like this:
You could also use this for bottom brackets and track hubs with the appropriate sized drifts.
The bearing themselves will come out when you knock the axle out of the hub.
You can send Hunt a message and they will tell you what size bearings you need. Might be quicker to just remove the bearings yourself and read the size. (Remove the end caps, pull freehub off, put a piece of wood over the axle and hit with a lump hammer)
Then you can search that code on google/amazon/EBay/your local bearing shop. You will want bearings from one of these manufacturers - NTN, SKF, FAG or NSK.