Do yourself a favor and start measuring this setup with metric numbers in mind. You don't say what type of equipment you're working with, but most seals, bearings, ball, bronze or otherwise are metric. Even here in the US. But still we'll all talk about "fits" in thousandths. Hard habit to break, as those are the type of numbers we see in our minds.
Just know that if you have say a 2 thou press fit of the bearing into the housing bore, that same amount is going to show up as shrinkage on your ID, and can easily lead to the need for working the ID after the fact, or the need to account for it before the fact. Just sayin...
A seal ID is not much to go on, as it is slightly compressed in use and difficult to measure with any certainty. There should be numbers on the old seal. Likely all metric. Go with them if you can read them. But like the one responder said, the seal bore and bearing bore can easily be two different sizes.
Ha... I see I just repeated a bit of what John Evens said. So yes, definitely things to consider in your quest.