Any good hardware store or paint store should have TSP.
#10611 1 lb. Savogran TSP is the most common brand and product number.
I sold it for 30+ years.
Cannot run a paint department without it.
Wierd, I just bought a 4.5 lb box from that auction site this morning. I hope it’s the real stuff. Same brand. Interesting how the net has sped things up so dramatically! We’re all criminals now!!