You don't need the developer role; you can just download JAXB jars:
Go to
https://jaxb.dev.java.net/
Press one of the big orange "Download" buttons; you will receive JAXB2_...*.jar
Run java -jar JAXB2_...jar; you will receive jaxb-ri-... directory.
jaxb-ri-.../lib contains the jars you want.
Matthias