Maybe something like this? Learning Resources Square Color Tiles, Counting, Sorting Toy, Set of 400 in 6 Colors, Ages 3+ https://www.amazon.com/dp/B000F8T9B8/ref=cm_sw_r_cp_api_glt_fabc_9S9TMWJZWQRYH01JZB36

I searched for plastic / wooden tiles on Amazon. Often you can find cheap options for items used originally for educational purposes, like teaching little kids how to count