Lighter conv backbone for faster-rcnn

Hi,

I am am attempting to train a faster-rcnn model using the method presented here: https://pytorch.org/tutorials/intermediate/torchvision_tutorial.html. I would like to use transfer learning considering my data set size is very small: ~250. I am wondering, is there a lighter architecture similar to fasterrcnn_resnet50_fpn with pre-trained weights that I could use for my case? Thanks in advance.