The new edition is 59 x 92mm.
The smaller square temple cards seem to fit well in the 63.5mm x 88mm with a 1 mm gap. You would have to shave them to be 63.5mm x 63.5mm though.
Does anyone know if Mayday or other companies make a 63.5mm x 63.5mm sleeve?
Not that I know of. Swan PanAsia makes a 65x65mm that would probably work decently. Part number SWN-031.