These shoes are Zoomies from
Dog Boots | Dog Shoes & Dog Booties. Toby has a pair and does great walking in them. If you can't figure out what size you should order, Karen provides excellent customer service. She is a member of YT (AllDogBoots). Just send her a PM or contact her through her website. Here is the link (but they aren't called tiny chucks).
Dog Boots | Dog Shoes & Dog Booties
Toby also has some Neopaws and Meshies from Karen. He had never worn anything on his feet either but after a few minutes he was walking like a pro!!!!