Eh, don't get me wrong... armour is nice, but it can be overrated sometimes.
You can always build it out of cereal boxes and duct tape and have fun painting it yourself if you really need to in a pinch. Heck, the Sarge (SSgt Burton) took existing off-the-shelve sports gear and painted it up to look quite the part at a fraction of the price.
You'll never be able to replicate a pulse rifle as easily or as cheaply.
My gut would say to go with the pulse rifle -- I highly doubt the upcoming cheaper knock-off will be anywhere near as close in feel, weight, and quality.
Plus, I thought I've heard something about a possible import ban of all replica weapons in the U.K., which I assume would include airsoft and model gun replicas as well. You may want to check into that and take that into consideration if applicable.
Just my .02¢
F.Y.I. This smart gunner breast plate...
[img]http://www.ripstick.com/USCM/images/Chestplate_Template.jpg[/img]
...was built in about an hour or so with nothing more than cardboard, duct tape, and spray paint...
[img]http://www.ripstick.com/USCM/images/Cardboard_Chestplate.jpg[/img]
Rick "Ripstick"
[img]http://www.ripstick.com/USCM/images/Ripstick_Aliens_Legacy_Banner_2007.jpg[/img]