I was surprised to see 2000-3100 psi pressure washers for sale at Walmart for around $200-$300. Is there any feasible (i.e. cheap) potential means of converting one of these to fill a scuba tank to 3000psi, or even direct fill a gun at 2000psi?I know there are chinese 4500psi air compressors available for ~$300 with shipping, was just wondering what technically would need to be done (if at all possible) to convert a pressure washer to air.