We upgraded to 1.000" torsion bars with front and rear sway bars for our 71 Valiant.
Have you tried PST or Just Suspension to see what they have?
We tried to support PST for ours (since they support FABO), but they were out of stock for their 1.030" torsion bars and could not tell us when they would be back in stock, so we called Just Suspension and they had 1.000" bars in stock.