The most likely bunt situation is R1/R2/no-outs, except if the three or four hitter is up. (I often call for a bunt in the latter situation; most don't.)
The above is even more likely with a LH batter at the plate.
A fairly common bunt-for-base-hit scenario is push bunts towards third by LH batters. With older players, and pitch speeds from 75-90mph, RH batter attempts to bunt towards third are low probability--often botched foul, or back to the pitcher.
As an offensive coach, I dedicate serious practice time to bunting, primarily for saccing with R1/R2/no-outs and for squeezes. I emphasize the importance of our projecting our ability and willingness to bunt because of its terrorism value (small threat, large effect).
Conversely, as a defensive coach, I minimize the value of the bunt-- to minimize its terrorism value. IMO, the no. 1 defense against the bunt is an athletic pitcher.
Lucky for my teams, most coaches talk about bunting but are reluctant to flash the sign.