1999 Tacoma 2.7L oil leak from timing chain cover

Hey all,

So I have had my truck, 1999 2.7L 4wd 5spd, for about 3 years now. Have done a bit of maintenance on it since buying, new clutch,flywheel, axle shafts, exhaust, etc, nothing much to the motor except routine stuff. My problem is I have an oil leak that has gotten worse over time, started out as a drip or two and now over 4k mile oil change intervals I probably add 1 - 1 1/2 quarts. Its leaking from the timing chain cover. I don't mind replacing it, however it's a big job. I have something else to drive so if it takes a month working on weekends its no big deal. I am just wondering should I go ahead and change all the components like timing chain, tensioners, water pump, etc, while I am looking at it with the cover off. Or is there any product that actually helps fix oil leaks. The mileage is 159,000 miles btw. Thanks