The stretched Type 45 was a BAE proposal for FSC. The "Baseline ..." designs are MoD in-house configurations used to allow exploration of options and to evaluate the impacts of capabilities, without being locked into a specific design. They sometimes appear in publications - the last was Baseline 7, in trimaran and monohull form, as a comparison of the advantages and disadvantages - Richard Beedalls' Navy Matters site has some images:
http://navy-matters.beedall.com/fsc-pre2005.htm
But, as I said, the designs have appeared in other publications, with various detail changes - this most closely resembles them in appearance - certainly it's closer to that than a Type 45, although it could be variant of the latter, or maybe neither!
I couldn't comment on the weapons outfit, but the illustrations have generally shown 114mm Mk8, some kind of 155mm-a-like, and more recently US 127mm weapons.
RP1