Sounds like you need to use getblocktemplate. If you do an http POST to http://gbt.mining.eligius.st:9337 with a body of:
{"id": 0, "method": "getblocktemplate", "params": [{"capabilities": ["coinbasetxn", "workid", "coinbase/append"]}]}
You should get a transactions to process. See https://en.bitcoin.it/wiki/Getblocktemplate for more information.
I can’t find many other sites that support GBT but there is a list of compatible pools in the above link as well.











