Magic64 would be your best option. Impressievly fast for a c64 emulator. Just dont expect too much from it. C64 emulation is quite heavy vs. most other 8bit machine. On the 50mhz blizz mkiv '030 I had some years ago I had to set it to every 3rd frame, and it still rarely hit 100% speed (about 80% on average).
Even my 40mhz '040 I can only hit 100% with sound disabled on all but a few things.
