As long as you get a bolt from the same era I will bet there is a 97% chance it will headspace. Eras: PreWar, 1936-1947, Transition 1946-1949, 1949-1952 or 1953 (These are late model bolts that the bolt faces were not recessed to do final headspace and they may go into 1954?? Definitely 1955 and later used less chamber reamers and did final headspace by recessing the bolt face.
In other words if you had an early gun that the chamber was fully cut and then burnished for final head space and put a later bolt in it that was recessed for final head spacing, it will have too much head space, possibly excess.
Now the chance of the bolt dropping in and functioning, i.e. cocking and going on Safe, is a different story. Most likely you will need a gunsmith to fit it if it doesn't function as a drop in. Post the first 3 digits of the serial number and X's for the remaining digits and we will tell you what year it is.
