See: http://tinyurl.com/44k7ev
Lizzie was known to "shop" there. de Mille in her book Dance of Death has this footnote on p106:
"Mrs. Gifford, Miss Winslow's successor at the Fall River Historical Society, told me that whenever Miss Borden entered her husband's jewelry store it was understood she was never to be left alone for a minute with any of the merchandise. Even so, she was able to filch items from time to time. They were added without comment to her bill and she paid without remonstrance, performing a neat act of oblivion."
I'm not sure I believe any of that. It's interesting to note that it says "she paid", not her father. Here's the photo:
