Then You tried definitely not much, I feel that I would have to take a lot of beer with me. You can look for some Polish craft You would like to try, ask other brewers (I guess You have some discussion group) and let me know in month or two. I would come by car, so I have some space, but I have to take something except beer also
Here the breweries with the best availability in my part of Poland:
http://www.ratebeer.com/brewers/alebrowar/14472/
http://www.ratebeer.com/brewers/browar-birbant/18698/
http://www.ratebeer.com/brewers/browar-kormoran/3893/
http://www.ratebeer.com/brewers/browar-olimp/17375/
http://www.ratebeer.com/brewers/browar-perun/19946/
http://www.ratebeer.com/brewers/browar-pinta/12742/
But You can also look for other, they are also sometimes available. One more thing, most of the beers are not brewed regularly, more like 2-3 times a year, so I am not sure if everything will be in shop, but earlier You start chosing something I could collect it when found in store.