B0147/S1 and several related rules have a simple period-two c/2 replicator, consisting of a block of two cells:
In B01347/S13, two rows of replicators can be terminated by a pair of cells to form a 4c/8 spaceship.
In B01347/S1, there is a small breeder pattern that leaves behind a trail of rows of replicators.
Replicators -- Cellular Automata -- D. Eppstein -- UCI Inf. & Comp. Sci.