Mitsubishi Challenger 1999: Oil leaks from engine

My 1999 Mitsubishi Challenger has a few oil leaks from around the engine. They might be from the rocker cover seals, and I have noticed a little trickle coming from the left bank and the oil appears to be burning over the exhaust leaving an annoying smell. The car has only done 155,000 km and has been really for the family and has never let us down. Should I spend money on it?