Hi folks,
I am looking also for Puebla avocado seeds if there is any available
I would be quite shocked if that one was available. I believe Brad (@spaugh on here) grafted his over awhile ago and I'm not aware of anyone else growing it, it's one of those old varieties that no one really grows anymore. I have one small graft from scionwood I got from Brad, but it'll be a few years before it is large enough to fruit, assuming either a few mild winters in a row or that I'm able to protect it well enough in winter for it to ever get that big.
I think in Europe, your best bet for hardy seedlings is to find out what the minimum order is from Viveros Brokaw (in Spain), as they offer many hardy options, both clonal and seedling. If enough people are interested to do a group order, you might be able to meet the minimum order pretty easily.