The size and situation suggest a good chance to skip surgery! - after all, it is not surgery as you seem to suggest! - the urologist
introduces an instrument from below and extracts the stone.
Having come down so far, it can come out too... Collect it, if passed - for analysis and future prevention guide lines
If one is prepared to tolerate possible pain and chance of infection - one can afford to wait
In the meantime, drink plenty of water - more urine to push down the stone
How old is he? Are there any other problems and medications?