After researching the various tail beacon light options, I ordered the Aveo Engineering MiniMax Ariel red beacon light:
https://www.aveoengineering.com/lsa-experimental-ul-kits-and-gliders/minimax-ariel/. As can be seen in Richard Howell's build log, the width of the beacon closely matches the width of the tip fairing mounting area, creating a streamlined appearance:
https://sling2.slantalpha.com/wp/?tag=fabrication#bwg30/272. I plan to wire the red beacon such that it is always flashing when the engine is running. The 3-in-1 wingtip LEDs will satisfy the requirement for white read-facing position lights, thus the position branch of the tail beacon will not used to avoid confusion with the red left wingtip navigation light. Input specs for the strobe are: 0.85A @ 14V (11.9W).