Hi
Is there any VDSL Router with ppp support for TalkTalk Connection?
I don’t seem to find any Milkrotik Router with RJ11 ports
Any suggestions?
Nope, no devices with builtin xDSL or DOCSIS.
Use your current modem bridged or some passtrough mode.
You can also do tests with SFP VDSL2 module, e.g. https://www.proscend.com/en/product/VDSL2-SFP-Modem-for-Telco/180-T.html But no promises 
Bridged modem or terminator from your provider will be likely the best anyway…
Inclusive GPON was descontinued, so, celular technologies are the only “WAN” Mikrotik products that you can find.
No xDSL
No Docsis
No GPON
No Vsat
Regards.
Something like a Vigor 130 would be a decent bridge modem. Should work with BT on default settings. Just need the correct PPP client setting then.