This reproduction sheet has been available for about 6 years. I bought one when first 'announced' for under $30. They had been sold on
ebay, properly marked, for the $50-60 area. so the rest of the price is mystical profit.
About 80% of the penny blacks can easily be plated by anyone. You can download the full Nissen set of images at:
http://www.philatelicsannex.org/ref...ference.htmlA few are very close in letter positioning, there it takes practice and an experienced eye.
For the Penny reds, there are other means, among them the Fisher-Brown measurement system. [Gauge and books sometimes appear on
ebay]. with that 99% of the blacks and 90% of the imperforate reds can be plated.