What about fpc-pdf, which is - certainly in 3.2.0+ excellent and comes as standard.
My understanding is that the losLab PDF library is written in Delphi's pascal and would have to be converted to Lazarus.
I do not recommend buying LosLab PDFLib because it does not work with Lazarus, and the seller, despite the promise of repair, has not responded to e-mails for several months