'29 Buick top irons are not the same as '30 and '31 ----- and in '30 and '31, the convertible coupe and roadster tops are very different. As far as the top bows are concerned, I believe that Rich Kesselring has the patterns. Call him at Oak Bows in Chambersburg, Pa. I don't believe that any other GM car tops are close enough to use on your Buick, but if you can find someone who will let you make patterns from their 90 series roadster you will be ahead of the game.