Honestly, what’s wrong with curly script PB initials? :-)

paperback by house

This better not be for one of those font identification games again.

- Lex

I am not sure it is Paperback, because this style does not appear on the font list.

http://www.houseind.com/index.php?page=showfont&id=171&subpage=viewfonts

Guess it is custom work by House Industries.

hmmmm… i guess i just assumed that these might be swash forms from the italic. one should never assume…