Also, for all you ebay shoppers and OE correct sorts..... Seat belts were not always from the same vendor from plant to plant, both of my 1970 & 71 LA built cars for instance, had American Safety Brand belts, while other plants (or different model years) may have used another Brand belt.
These unique vendor codes were also printed on the labels along with the belts application part# and date code which each belt had sewn onto it.
There is a guy in Utah restoring and selling belts on ebay for big bucks, but be cautious if details count to you because one set I saw him offer was a mess! Various brand name chromed buckles and latches mixed together to form a set and wrong tag data, etc. They looked nicely restored but WAY incorrect if you were going for OEM correc t details.