This one: 1st Edition Timeline: Let’s Iron It Out? It does contain the “Sets where Unlimited is rarer than 1st Edition” list.
The rarest unlimited edition Japanese set is hands down the L1, and L2 and L3 are UED are very rare as well. I’ve never even seen a picture of the UED L1 Pikachu, let alone had the opportunity to buy one.
The World Championship packs and Skyridge set are also rarer in UED compared to 1st.
Although the opposite is true of other languages, in Japanese sets, UED is almost always rarer than 1st (except for Theme Decks, for which 1st edition is usually rarer).
I’ve made a similar post in this thread.
Greetz,
Quuador