There are various manufacturers of glass fabric/thermoplastic matrix sheets. Most products are PP, PA, PU and PPS. See Twintex (from Vetrotex), Versitex, Cetex and Tepex (you recognize these products by their name, they all end up by "tex").
In PET, the only I saw in the past (in a conference, so I'm not sure they have the commercial product) was made by Polystrand.