A lot of it depends on your volume, too. For just a couple boards you use yourself, just manually tweak the osctune register to adjust the oscillator. (Assuming they will see a consistent temperature.)

If you are shipping them out, and if you have code space, you could put in an oscillator calibration routine. You'll need a reference, though--either an on-board crystal, RTC, or incoming serial data.

You also might be able to "guess" at the osctune value by reading the pic errors in reception. Look it up in the datasheet.

But the easiest is to add a real crystal.