I found an online shop that specializes in parts for vintage appliances and ordered two sets of gaskets, one for now and one for the future. I plan to keep this blender for a long time. Both sets cost just under $14, delivered. The blender was repaired for less than $7, with the other $7 set safely taped inside my main cookbook where I will see it often.
I didn't drive around looking for a replacement, so I saved gas. No raw materials were used to produce a new blender or wasteful packaging (only the gaskets and envelope they were mailed in.) And I still have that classic green model sitting on my kitchen counter. Win, win.