I have a Durst Laborator 1000 enlarger, and need an otopfe 6x7 negative holder for it. I have the following otopfe negative holders available for trade: 6x6, 6x9 and 314. The latter has an opening of 3 inches by 4 inches. The ones I have are almost new, and in their original wrapping. If anyone has a 6x7 they don't need and aren't interested in a trade, let me know.