If you believe that TjMax=105C for your 45nm E7200 then you can use that in RealTemp. Personally, I don't believe that for a second. Everest also uses TjMax=105C for my E8400 and after this test, I don't believe that either.
Here are some comments from the programmer of Everest:
And here is some more testing of a 45nm E8400:
TjMax=105C is only documented for the Intel mobile processors. There is no documentation from Intel that says it is relevant for any of the desktop processors.
The default TjMax used by RealTemp is based on IR thermometer testing. Read the documentation
here on TechPowerUp and try doing the calibration test. You will likely agree that it is impossible for your E7200 to have a TjMax=105C.