The Eleph Rappy was originally from the SEA version, so they have a different drop table to others much like the Drago Rappy (also from SEA). I had jotted down their drops in JP when it appeared, but I haven't heard about its global drops aside from the camos the PSO2 Global site listed.
These are my notes from JP & Do be aware they may differ from Global's drop table.
Dio Serpent Series (Red & Grey standard 10* weapons)
Welk Series (13* weapons that normally drops from Platidrahs & other Esca-Falzspawn) Confirmed in Global
＊Miracle Magic camo - Launcher, Sword, Partisan, Double Saber, Katana, Rod, Wand, & Jet Boots (appeared in Global's Halloween 2020 Bingo [Back]) Confirmed in Global
＊Felicity Edel camo (Felicate Edel- JP) - Harmonizer, Sword, Twin Daggers, Double Saber, Katana, Soaring Blades, Gunblade, & Wand. Confirmed in Global
＊Let's Go Ocean camo (recolor of * Let’s Go Summer, but multi-type) - Wired Lance, Knuckles, & Jet Boots. Confirmed in Global
＊Chocolate Emblem camo - Launcher, Wired Lance, Twin Machineguns, Talis, Wand, & Harmonizer. Confirmed in Global
- Global has stated Eleph Rappies drop the following items (level not specified)
＊Evil Shioinaru Yanpe camo - (All except Harmonizer) normally drops from Rainbow Keys & Death, Destroyer of Worlds LQ/Trigger (Space Magatsu)
＊Randall Orbit camo - (All except Harmonizer) normally drops from Mining Base VR
＊ Sorcerer Morus camo - (Double Saber, Rod, & Wand) normally drops from Rainbow Keys
＊Cydstrid camo - (Sword, Twin Daggers, Katana, Soaring Blades) normally drops from Rainbow Keys, Risk Exploration: Lillipa, & Descant Drahl (Lv. 91+)