Welcome to the Community @Pat4
How old? Note that 2G is gone and 3G will be gone beginning in 2024.
This other topic should be helpful
The Aldi Value Pack at $99 is something to check although can only be purchased in-store when offered 2 or 3 times a year. Some other MVNOs have similar offerings. The unlimited nature of calls and texts is a safety net of sorts and assuming he will need a 4G (eg newer) phone soon there is some data.
The other option is a PAYG per call and text plan that could cost even less in a disciplined use setting.
Others may have additional or different perspectives.
