HalionSonic7 is for free!
For everyone who may need it:

https://www.steinberg.net/vst-instruments/halion/sonic/

But only VST3. Since PG has not implemented any VST3 support since the first VST3 in 2008, you have to use vst3shell_v1.2.1.

https://www.xlutop.com/buzz/zip/vst3shell_v1.2.1.zip