Fantazia

Hi all I have been a long time reader on this forum and have learnt alot in the past few years from everyone so thankyou. For the first time ever i have not been able to find an answer to my question from old topics, so here is my question. I love making melts/tarts in portion cups but packaging is harder to come by in Australia, I found a company that sells the cups in PP plastic but the lids that come with are P.E.T, so I am wondering do the lids also have to be PP plastic or is P.E.T ok for the lid? Any comments would be greatly appreciated!