Pewter

An assortment of English Pewter, some of the tankards have stickers on the bottom that say George IV.  The shot "C" shows a broken glass bottom of one tankard.  I think it was passed down through the family because I can't think of someone buying it in this condition.  I have seen some online apparently of similar age but far cleaner and with more intricate designs, these seem plainer.  Would these polish to silver and if so should they be or left like this?  I guess I'd like an approximate range of what some could be worth, there seemed to be a lot available on ebay etc. and not very expensive considering the age.

Thanks 

Poor