https://plogue.com/products/chipsynth-c64.html
From the website :-
The free download will play for 10 minutes before stopping, long enough for a single in-game sid.Plogue chipsynth C64 brings forward the deepest SID sound chip emulation ever. The fruit of years of laborious research, it bears our legendary desire for emulation perfection. Real chips in the field vary wildly in sound - every slight deviation in silicon composition radically changes the character of the filter - and we went all out on capturing this.
We reproduced no less than 32 different SID chips in excruciating detail, covering the full rainbow spectrum of SIDs: every revision of 6581 and 8580 from R1 to R5, every tone from warm to bright to clean to distorted and gnarly.
This is a full, REAL emulator that can actually play original songs natively and accurately, with a full-featured SID file player capable of playing even exotic songs with multiple-SID setups, sample playback and hard filter overdrive.
They said it was all bleep bloops. But it's GOOD bleep and bloops! And we couldn’t be happier. And, as always, no samples are used, it's all true emulation!
https://www.youtube.com/watch?v=pePq68HaI7M