Buick changed the prices of the options during the ‘72 model year so the option price depends on when it was built.
...while researching '72 Sloan data to help document my '71, I recall learning that '72 prices were same as late '71 thru 12/11/71, then lowered due to a tax being removed/changed. Wish I could lay hands on that info. Prices could have been revised again after that date, but for my purposes, that was all I needed...
There were 3 price lists for 1972 -Beginning of model year -Dec 11, 1971 -Jan 13 1972 The beginning of the 72 model year prices were the same as the end of the 71 model year. Sometimes the window stickers had previous date prices even if the build date was for example 12/14/71 (price changed 12/11/71) because the stickers were printed ahead of time. It can be confusing figuring this stuff out.