Unfortunately they only come in OTP and ROMless, but if you are only looking to update a few variables, you could strap on a serial EEPROM.

But don't EEPROMs also have a data retention problem at high temperatures?
It's so hard to find reliable data. Does anyone have a link to specifications about data retention time of EEPROMs and EPROMs. Data about FLASH memory is available. Have a look at datasheet of ST62T00.

Thank you,
Kai