No. Sony ceased PS2 hardware production in 2013 and stopped pressing new PS2 discs years earlier. You will not find factory-sealed SingStar PS2 titles at retail.
None. SingStar PS2 titles were never released on PlayStation Store. The PS3/PS4 SingStore servers shut down in 2020/2021. For karaoke today, use Let's Sing (multi-platform) or UltraStar Deluxe (PC open-source).