Did Both
I had the same problem.
I first replaced the bearings with success, but about a year later I noticed a slight leak again and also that the pump would not hold a prime. After examination it was found that the impeller had worn a grove in the face plate of the pump housing, breaking the suction. When I pulled the shaft I noticed wear on the shaft and decided it was time to replace the whole pump. Cost installed was about $200.00. It is very easy to install and I would have done it myself, had I the time.
I would'nt fool with it. The pump is cheap, easy to install and if it goes it could be at the least, inconvenient and at the most, very expensive.