where is it leaking from? Try tightening the hose clamps first and see if that helps.

You can replace the hosewithout removing the pump if you buy the mb part (not oem - too stiff), and you are very patient about working the hose through the narrow gap with blunt tools. There isn't much room but a couple people have been able to do it. Replace both hose clamps, and be aware that all that trauma to the hose will probably shorten its life.

Another option is taking a hacksaw to one of the pipes and cutting off a quarter inch or so to give yourself more room. Be sure not to let any filings into the water passages (!).

Finally, the water pump r&r isn't too bad, it just takes a lot of time. If the belt has to come off, be prepared to replace the belt tensioner.