Not sure if I could recommend switching without a flush. However, if you are willing to take the chance, then these are also made my CCI, who makes the Toyota Super Long Life. They likely are similar and compatible, but are dyed
- Nissan coolant (not sure what they call it)
- Honda coolant (again not sure what it's called)
- Subaru super blue
- Mazda FL-22
but, like the Toyota SLL, they are all premixed, and probably priced similarly. So no advantage to switching there.
However, also made by them and available in concentrate are:
- Ford Specialty Green (said to be identical to FL-22)
- Golden Cruiser (may be concentrated, but no idea where you would even find this stuff)
I'm not sure you'll see a big price difference with the Ford Specialty Green. I am getting ready to do a drain and fill myself, and inquired about pricing, in case I was short (thought I was going to do it when time was tight, and a Ford dealer is only a couple of minutes away, but never did it in the end). Concentrate gallon jug about $38. Toyota SLL diluted gallon jug goes for around $24. Slight price difference, but not huge.
Based on this, simplest and best to stick to OE.