You can do it yourself dude to save money,
Strip the rad out and and get a hose adaptor to fit from your outside water hose to the bottom inlet of the rad and fill it up then when its full (keeping the top connection at its highest point) put a blanking plug on the end inside the outlet hose of the rad. If ya get what i mean
you will get somewhere between 2.5-4 bar pressure of a normal tap pressure middle of the day is best as most people wont be using showers etc for highest water pressure.
just wipe the rad down dry and you will soon see if its spurting out any leaks probably squirt you in the eye