I attempted to buy some Seal MT 5 dry mount tissue from Freestyle, but it been deleted from their catalog...and then from Adorama which doesn't seem to have it either. Has this stuff been discontinued? (I was finally getting some expertise using it and still have a small quantity, but I need more.) If MT5 is gone, does anyone have a recommendation for something at least as good? I would prefer a tissue that bonds during heating rather than cooling. The MT5 was permanent I believe....are removable tissues just as secure? I'd appreciate anyone's suggestions. Thanks!