Nicaragua Scott 3-7 Reprints?

While going through an album I had recently purchased, I found these imperforate Nicaragua stamps. I've only seen these perforate, and I guess I'd just like to know when these may have been printed, and maybe even by who, since they're probably fake. They have a very clean gum, making me even more curious as to why the printer left them imperforate. Why not just go all the way toward an accurate copy?

Cheers!

Edit: I always saw the word rouletted but I'd never been faced with identifying a rouletted stamp. Thanks for the swift responses!

Why not Scott 8-12, which are roulette?

They are Scott 8-12, rouletted 8.5. Whether or not they are reprints I cannot say. Originals have thin white gum.

Sorry John. I was writing at the same time.

Oldbold, notice that there are tiny tear marks where normally perforations would be. That indicates rouletting. Am imperf is generally cut with scissors or something else leaving a straight/clean edge. Once in a while, you'll see stamps that should be rouletted that are trimmed on purpose to be imperfs; maybe by someone looking to improve the edges.