I really love these gem-based HDRI images that I purchase from Daz3D:
https://www.daz3d.com/iradiance-crystal--sparkle-rich-hdri-for-iray
They are also on sale right now for 72% off!
They make for fantastic backgrounds for pinup images and provide a really good base for the lighting as well. Please note that the HDRI is not the only light in these images though, if you were curious about that. In addition to the HDRI image/lighting, I'm also using a 3-point light system surrounding the model.