There are plenty of places depending on the part you need:
http://www.szd.com.pl/
http://www.szdjezow.com.pl/index1_eng.html
http://www.nowakservice.pl/
http://www.marganski.com.pl/
http://www.puchalski.ig.pl/
http://www.avionic.pl/
All in English with people willing to coperate, ordered canopy for
Puchatek once from SZDJezow.