Possible bad ignition cylinder - '92 RMW

The key will turn, but it won't go to the start position to crank the car, as if something is blocking it. just happened out of the blue. the key is pretty well worn, so I'm thinking a new cylinder is in order. Any other thoughts as to what it may be?

You may have a broken fork in the column. It could also be the electrical switch on top of the column about half way down. It is infinitely easier to work on if you can remove the column from the car. Sometimes it is easier to replace the entire column with one from another car. If you get one with a key, you can use the new key, or replace it with your original one (if you ever need a key from the dealer the original key can be duplicated without having the key). Any column from 92-96 will work, but you may have to paint the bezel to match. The VATS connector on the 94-96 columns will not affect the rest of the functions, and can be ignored. You can use the 91 column, but you will lose the "press brake to shift" function, because the solenoid for the function is not on the 91 columns.