I am having some trouble with my wheel bearings, about a month ago I noticed a bit of slack on the rear wheel and then knocking so I took the bearings out to find that there was a lot of water in there and rust on the cones and hub. I went up to Halfords and got a bearing kit front and back and some waterproof grease and cleaned the cone and hub with steel wool then replace the front and rear bearings. At the weekend just past I looking over the bike after using it during the week that I noticed some knocks from the bearings on the rear wheel so I took the hub apart once more and noticed its all mucky and the water has got again. So I repacked them with grease but this time I noticed that there is more ware on the bearing and cones on the cassette side as they have all went to gold from silver which tells there has been some heavy friction going on due to water getting in. I am thinking it maybe the seal on the hub? So should I just get a new hub kit with new seals and cones or just use some sort of sealer? I don't want to be doing this every 4 to 5 weeks. Just to note I do cycle in the rain and try to keep water of the hub/bb area when washing the bike, they cones are not too tight or slack either. So where abouts can I get wheel hub parts apart from Halfords that include the seals as I prefer to do all my repairs myself if I can without going to the LBS.