With such a network difficulty, solo is unrealistic

Why not? If the pool with 150kH/s can have 20 blocks per day. So my private pool with 15kH/s should have 2 blocks maybe more if I will have good luck.
I totally ignored the initial question in my previous reply. You should be good with the pool you have installed, I used the same one. Found one block, but used the wrong Sumo wallet for payments and fixed that. What is your "pool_info.log" saying? It should be something like:
2017-11-29 04:20:55 (Thread 1) Block e5ded9 found at height 75025 by miner Sumooxxxx - submit result: {"status":"OK"}
2017-11-29 04:20:56 (Thread 1) Blockchain height changed to 75025, updating template.
2017-11-29 04:20:56 (Thread 1) New block to mine at height 75026 w/ difficulty of 514456742