You don't really need any special tools, just some brute force. The special tool they may be talking about is the one used to pull the axle back through the hub/knuckle, but this tool is not an absolute must.

Also just cause your boot is torn doesn't nessescarily mean you need a whole axle. Was there noise? They might just be trying to upsell.

Also if it is just the outer boot that is torn there is no need to do the inner boot. You don't have to remove the axle to replace the outer boot.