You'll only find out what VM will offer your by phoning up.
VM will try and force you into taking a bundle, generally by making the standalone broadband price unattractive against the discounted bundle.
Worth noting that standalone services (e.g. broadband only) have been showing as 24 month contracts recently on the VM website. Also factor in the baked-in price rises each April.
If you want broadband only, you may well be better off going elsewhere and getting new customer pricing, even if this involves a lower speed.
Check out any Openreach availability of FTTP and alt-net offerings in your area as alternatives to VM.
If you haven't switched provider since 1997, VM might safely assume you are unlikely to move and pitch its offer accordingly!