Can I use a 15 amp receptacle on a branch circuit fed by a 30 amp breaker?
It's only a 20-amp branch circuit if all the wires are 12 AWG or larger.  If there is any 14 AWG wire at all, it's a 15 amp branch circuit. 

To get a UL listing for a 15A receptacle, the maker must rate it for 20A of pass-through.  (pass-through is where you use the two screws on the receptacle to continue a circuit, rather than pigtailing.)  The purpose of this rule is to make it legal and safe to do exactly what you are doing. 

So, yes.  It will be fine.