Children’s book I read kindergarten, class 1971. I don’t not know title but I think the main characters name is pandora a cat. It is possible name is in title. My memory pictures a grey and yellow cover w cat and it’s magic collar. It tells the story of a cats nine lives which is actually 9 times to teleport. That way cats are suddenly in the room. I believe the collar was the way “pandora” traveled. When I was an older grade schooler I went back to class room to find it, that’s where my visual memories come from and cats name, but the storyline memory seems solid since that’s how I found it the first time.
How about this one?
https://www.kirkusreviews.com/book-reviews/don-joan-caufield-2/never-steal-a-magic-cat/
https://www.goodreads.com/book/show/8486157-never-steal-a-magic-cat
Time Cat, Lloyd Alexander’s first book, might be worth investigation.
https://en.m.wikipedia.org/wiki/Time_Cat:_The_Remarkable_Journeys_of_Jason_and_Gareth
It’s Never Steal a Magic Cat. Published in 1971, cover as you described, and the cat’s name is Pandora. I had the same book; https://www.kirkusreviews.com/book-reviews/don-joan-caufield-2/never-steal-a-magic-cat/