No colon necessary. Use a period/full stop. And maybe a comma after available. There's an implied it's in there between If (it's) available that some might want you to include, but it's clear enough without it.
The proper spelling is carries.
Nitpicking: Since you are capitalizing Aspirin, you are referring to the specific brand name by Bayer of A.S.A. (acetylsalicylic acid) , so you needn't ask Mike who the manufacturer is. It's Bayer. If you didn't capitalize it, then you'd be in a market where aspirin is used as the generic term, and there are several manufacturers of that product.
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