If the TDP of the processor is the same or at least 10% higher, you should be OK.
I've done the same with my old M51TR that come with the Turion RM-70 for the ZM-82, one of the also supported CPUs.
The reason I say that it's because the laptop could have different cooling apparatus regarding the CPU installed. So if the TDP is the same, it's OK, if it's 10% it's also OK, the cooler should hold it, with sightly higher temperatures.
If it's bigger, then try to find the part no regarding the new cooler and try to buy it.