Take a look at AC 20-165 under the section "Position Source". Position source is the role GPS plays in ADS-B. The AC does not list, to my knowledge, equipment meeting the requirement, but rather the requirements the equipment should meet when used as a position source. Then you can make your decision if the 430W meets those requirements (in this case, it appears TSO-C146() is proper). If installed per requirements, you'll likely find that it does (Garmin lists the 430W as TSO-C146a compliant in the sales ad I'm looking at). Keep in mind the rules for ADS-B are currently limited to OUT only, meaning there are no regs governing IN. Furthermore, the OUT regulation is not effective until January 1, 2020. (91.225, 91.227) Hope this helps.
http://www.faa.gov/documentLibrary/m...7;2020-165.pdf