Yes, the Gallery images are fine.
Picture, or Souvenir, weights of the type you show range from 19th to early 20th century.
As far as I know, there is no formal literature on these as they are very common and are at the basic level of gift items. It might be fascinating if somebody was to produce a book covering the types of these weights and some of the history about the places or characters depicted, but I doubt that will happen as there are so many and the subjects are so various.
As for value, not a lot. Currently, searching eBay for "souvenir paperweight" (to limit the hits to a manageable number) shows some in the USA with starting or buy it now prices from $5 to $10. Another in UK has a buy it now of £10.