In B01367/S01, a 1x2 block forms an unstable replicator; it can be stabilized by making four copies of itself, forming a 10c/20 replicator.
These replicators can be stabilized by pairs of small oscillators, making larger replicator-based oscillators. The one below has period 60.
Replicators -- Cellular Automata -- D. Eppstein -- UCI Inf. & Comp. Sci.