What is the SOTA for 2 stage object detectors with smaller datasets?

Wondering where I can find information on what 2 stage object detector is considered state of the art. I am looking for a model that can be trained with a relatively small dataset (10-20k images) and works well on small objects (a golf/tennis ball for example).

I've tried using single stage models like YOLO and SSD but they don't seem to work as well as I would like. Inference speed is not a particularly large concern, but a reasonable \~5FPS …

art computervision dataset datasets detectors example golf images information object objects small sota stage state state of the art tennis