Congratulations on your new purchase ….got a photo of her ?
Now to be very honest with you the SC430 sat/nav is not that good compared with a tomtom or google maps on your phone.
If you want a newer sat/nav disk it can be found in the boot , right hand side, pull grey cover off, slide the left switch over and press the button.
The disc will slide out and if like my 2007 SC, the disc will be around the same age .
New disk from Lexus several hundred pounds.
a copy disc off eBay ..hit and miss if they work !
See here…..
https://www.ebay.co.uk/itm/235256085922