You can look at pics on eBay for any unit where you can see the black DAB antenna connector on the back above the fan and note down the part number. The last maps for the RNS510 was 2020 and it is unlikely VW will be releasing any more, so that is something to consider.
A lot of people are getting NONAME RCD330 or RCD360 which are great little units for between £200 and £300, they have CarPlay and Android Auto, so you can use Google Maps, Apple Maps or Waze; all far superior to VW maps. Though most models of this unit have bugged RDS station info.
The ultimate is Discover Media STD PQ (revision G), which is a VW unit in later cars like the Amarok, but they are around £700 (with Component Protection removed) and require a lot of supporting mods like CAN gateway >AN, later cluster (if you want cluster integration with the head unit) and possible camera/park assist upgrades as well as a new USB/Aux port and supporting cable.
I hope that helps
Stu