Premium Bandai has recently updated with the official release page of the upcoming Die-Cast Zyudenchi set. The set includes all the main 23 Zyudenchi along with the Tobaspino and Super +1 Zyudenchi. Keep in mind these are non-DX roleplay functional so they are made for display purposes.
Preorders for the set is currently open and the set will be released in September priced at 15,000 Yen. Those are interested in the item should contact your preferred middleman for more details.