I just use regular sheets. Most of the time consuming work is removing the old glue from the neck and really cleaning it to provide a good base for the new cork. Hammering the sheet with a ball peen is less than a minute, adding the bevel to the leading edge, another 30 seconds. The really time consuming step is letting the contact cement dry. But it does take a little bit of skill to line up the new cork with the tip of the neck, once you start, there is no going back.
But I've done it so many times now.
One caveat is the quality of the cork sheets. You can buy a 10 pack off Amazon and there are maybe two good quality sheets. And sometimes you get 7 or 8 but it's unpredictable.
How are the cork tubes in that respect?
Oh, and you can always use the Valentino cork from MM or buy it for a fraction of the cost from 3M, it does stay elastic/compressible for a long time, peels off easily and is easier to apply because you can correct the alignment. But it's too wobbly for me.