What "engineer" was this and why did they suggest you "need" a new box? TalkTalk have not provided anything other than non-recording boxes for a while now, so I can't imagine this would offer anything over and above what your new TV is capable of.
From the 29th of March our TalkTalk Community will move to peer-to-peer support and the TalkTalk team will no longer be here to support with queries. Don’t worry we still have plenty of ways to reach out if you need to speak to TalkTalk directly. For more details check out the link here: How to contact TalkTalk Broadband - Help & Support.
