The URC6820 should still be available. The URC8820 or URC10820 will also work and are shown in the link below. [Link: ofausa.com]

The RM-V11 may have come with the TV but it is not the remote for the TV. It is a universal remote, which is why it will not work your TV. Sony quit using that method of changing the channel lineup many years ago so current universals don't have the proper commands any more.

Here's a link to the manual for the KV-27TS20, so you can see what the correct remote looks like.
[Link: 129.33.22.12]