I know that google can find them also but here you have list of enigma simulators all on one page (please comment of more that should be added).
- a online key chart generator that can create unique or reproducible keys is on this site over here
Physical replicas of different levels of authenticity:
- Arduino enigma: https://www.tindie.com/products/ArduinoEnigma/arduino-enigma-simulator-simulates-enigma-i-m3-and-m4-machines/
- enigma-e, designed back in 2003, sold at bletchley park shop http://www.bletchleypark.org.uk/shop/p.rhtm/130853/795875-Build_your_own_EnigmaE_Kit.html
- a kit based on arduino mega http://www.stgeotronics.com/