Yes, the substitute 89-300ce refers to is the same thing as Enviro-safe (a Hydrocarbon or HC, it is marketed under a whole bunch of different names but is the same thing). It is a mixture of propane and isobutane, I think.
I also believe it is completely legal to drop the HC on R-12 systems in Canada.

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1999 Porsche 996 Carrera Convertible
1994 420E - SOLD
1986 300E - SOLD, what a car
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