You may have to have some made. It wont be cheap, but a good machine shop should be able to fill weld a set of wiper arms, and drill them out on a taper to fit your truck. Also you may be able to find some for an old Ford, or Chevy that will be close enough to fit. It will take some research to find something close. Or maybe even something for a classic import from the 50s. Like maybe an Austin Healey or something like that.