I tested this circuit after the arrival of my order for 10 BS170, and it bench tested OK!
Note for newbies, I hope you realize this circuit could be the precursor to a multivibrator, with this circuit you have to change states by hand because of the components missing for a full multivibrator.
When starting the simulation assumes equal current flowing on both sides, you have to press one of the push buttons to latch it on.