Can I replace the other equivalent product with NJM555?

It is possible to replace the other equivalent product with NJM555.
Please be sure to confirm every characteristics on your application with NJM555.
Especially, you should confirm a temperature and frequency characteristics of your application. However, some other equivalent products might be different an output stage and frequency characteristics of NJM555.
Let me add that NJM555 cannot generate a frequency of 50% duty.