This week the Montreal Protocol arrived at my front door when my heat pump needed four pounds of R-22. Due to restrictions on import and manufacture, the wholesale price of R-22 has risen above $10 per pound. Apply the typical 5-7X retail markup for delivery and installation, and R-22 is getting expensive!
It's true that R-22, which is now being salvaged from old air conditioners, will be available for at least the next several years. The question is what price will R-22 reach, as manufacturing restrictions are tightened further. Essentially, the Montreal Protocol is coercing us to drop R-22 without prohibiting it immediately. The wealthier you are, the longer you can wait.
EPA does not allow a consumer to buy R-22, so I cannot hoard it at home. As far as I know, no one is running an R-22 "bank" where a consumer can prepurchase R-22 to be held in a dealer's inventory for future use. Perhaps the EPA would not permit that, either.
Keep the heat pump but replace R-22 with another refrigerant? Difficult, risky, and probably expensive. Most new heat pumps use R-410, which does not threaten the ozone layer; but R-410 won't work in a system designed for R-22. Some online sources say that R-407 can be used to retrofit R-22 heat pumps, but a complete purge and interior cleaning is required -- possibly a new compressor, too. I can't find any HVAC company in Raleigh that advertises experience in R-407 retrofits. And why should they? It's easier, more profitable, and less risky for dealers to sell new R-410 heat pumps.
My heat pump is only five years old. I suppose I'll throw R-22 at it until I can't afford to -- and that might be only 12 more months.