It was around $70. Have to find the receipt.
I had called the day before and asked and also called back the day of and asked again. Since I work downtown now I normally don't drive so if they didn't have any or were going to not exchange I was going to go back to Linde. The last time I went they had run out and were have a shortage of the small bottles. This time they were low but had about 4 bottles or so left. I was in the middle of building my front bumper so I went and exchanged at Linde. The guy at AirLiquide remembered that I had tried to get some last time which was impressive since that was like two years ago this September.