I was sent free seeds last year for a smaller, round, red tomato called Early Doll. Was a great performing tomato, averaged 4-5 ounce almost perfectly round tomatoes with pretty decent taste. I don't remember having any problems with cracking or splitting with them either. Each plant was very prolific, averaging about 10 pounds or so of tomatoes per plant. The only place I know of for sure you can get them would be at
https://seedsnsuch.com/ Hope this helps