There is some good news though, if the rifle has a factory barrel and the chamber has not been modified, the likelihood that an after-market bolt will headspace properly is high. Take it to a 'smith that has the gauges and get it checked or invest in them yourself. Brownell's has them and if you plan on doing much of your own work, or shooting a ton, it may not be bad to have them in your toolbox. If you do need to have the rifle/bolt headspaced it isn't usually that big a job. It's just a matter of finding someone that won't take a month to turn the job around.
I recently bought a new bolt for an old 1903 Springfield. It was a NIB bolt and when I slipped it in it fit perfectly. Headspace was right on as well.