I've got an oil leak on a steering box output shaft. The radial lip seal has worn a groove and there is some corrosion around the area. I've tried to sand it smooth and replace the seal, but it's only made it worse. I need a permanent left-field solution (a bodge in other words). I've heard of devcon or belzona being used to build up material on shafts, but these don't come in small quantities. What's the cheapest stuff I can use that will do a good enough job?