Diesel Timing Belt Question

I put a belt on about 15,000 miles ago. My fuel pump shaft seal has been leaking for about a week. I havnt taken the cover off yet, however there's a fuel mist under there I can see when the engines running. . I can change the seal by taking off the drive gear only, and not the pump bolts, and probably only have to check the timing, but not have to readjust the timing if I use the same belt. If its OK to use the belt. Or I can put a new belt on and have to time the pump,completely , thereby having to take off the valve cover and lock everything up,and everything else that goes along with it too. I have all the tools and books, I have the dial indicator too, But its much more work, and its nasty out here now. Should I reuse or change the belt, creating much more work. Thanks.Vern