I am saying that I 'THINK' mine is continental europe, and there is a good chance yours are also the same.
I have found other pieces that were souvenir glass items made in vaseline glass when tourists went to 'the mineral baths' or just taking holiday. The pieces from Boston and Sandwich are so few and far between that I think they were made for personal gifts, not a general production item. With me having a book that says souvenir on the piece, it tells me that it was a regular 'for sale item'. added to all that.....the ones shown in the BARLOW AND KAISER books are very very tiny. The book shows 12 different versions, some only fragments, AND THE BIGGEST one is 2" tall. All are very plain, very little decoration to them, very little cutting, etc. one is shown in canary that is 1 18" tall.
the narrative from the book: "Unlike the larger cut book paperweights, little books were not a commercial product. Glass cutters used pieces of broken annealed glass, cut them into rectqangular blanks and then made the cuts that would turn them into little books" BARLOW & KAISER, photo #3366, A GUIDE TO SANDWICH GLASS: WITCH BALLS, CONTAINERS AND TOYS, copyright 1987 by Barlow and Kaiser.
no large ones were shown in the above listed book.