I wish the model 61's were as plentiful on eBay as the 28's. They were manufactured at the same time, but the 28 outsold the 61 in an almost 3 to 1 ratio. I guess there was a significant difference in cost. In addition to the metal top, another rarity for the 28 is finding one with the original disposable bag system. Somebody posted a photo of one on here a couple of weeks ago....