Transfill adapter. If necessary, rent a tank, transfill, and then return the rented tank. I don't do the VIP/Hydro tax on any of my pony-bottles. I built a transfill-adapter using 2 parts from
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I think it was about $40 including shipping, and just waiting a month for the arrival.
edit: You could also use that tank you rented for a slightly-shorter shore dive, if your schedule allows for it. Generally speaking, transfilling from a full AL80 to an AL19 gets the AL19 full-enough. I'm generally not doing anything too extremely on vacation dives, so 2400 PSI in the AL19 is plenty for my redundant air supply.