Six weeks ago I paid $9.99 for a 12 oz. can of R134a. Today I paid 13.99. Pep Boys both times. Has there been a general price spike, and if so why?

What's my best source for those 12 oz. cans?

Thanks.

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14 E250 Bluetec 4Matic "Sinclair", Palladium Silver on Black, 160k miles
06 E320 CDI "Rutherford", Black on Tan, 180k mi, Stage 1 tune, tuned TCU
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