Hello Carolyn: The weeping form I am familiar with is grafted using the species for the trunk. Its flowers and foliage is identical to the regular plant. Its intial height is determined by the height of the the trunk, often 6 or 8 feet from the soil line. It would be perfectly hardy in East Moline. You could try an internet search on either Weeping Pea Shrub or Caragana arborescens "Pendula" and see what you find.
Sincerely, Richard Hentschel