besides cdn.satellite.earth I don't know of any ones that are public. although if you have nodejs and npm installed you can easily run a local blossom server using blossom-server-ts with "npx run blossom-server-ts"
https://github.com/hzrd149/blossom-server?tab=readme-ov-file#running-with-npx
There are also a few other implementation that might work locally too