Hard to come by !! Try virtually impossible ! AAW, shucks! Where were you a month ago. My searching yielded nothing, except...
Burpee marketed (this year? - I'd never seen it before) a lima they call "Big Mama". It sounded just like the good Doctor, so I got enough for three seasons (fail safe). Would you be interested in a fair trade, just for research... If we can prove Burpee hijacked the breed, imagine the lawsuit :lol !!
If not, do you think you'll have 'em again next year? I wouldn't want to get a mixed breed in the next generation.
For anyone else interested, go for it!! I had these for about five years, until the mice wiped out my seed stock. My best gardening buddy (doesn't everybody have one?) moved upstate, and he lost his stock that year, too. Been grieving for two years, 'cause those were magnifique - five of 'em makes a meal! Heavy yielder, too. Only 16% made it to the table, 'cause they're delicious raw, too.