Sure, no problem for bulk...let's say £1.50 each + post. Should save about a tenner.
Silverline (the cheaper one) is probably OK for a small job, but personally I'd go for the Sievert torch for the extra cash. Swedish quality rather than the Chinese copy. They're top quality propane torches, and have great support and range of options (http://www.cupalloys.co.uk/heating-c107.html
The 2941 burner's a pretty good small burner for braze-ons, you'd need something bigger for lugs etc, preferably one of their cyclone burners, which spin the flame to wrap it around the tube.
Also, an upgrade to the 3488 handle, with the cut-off pilot light trigger is well worth it.
Bigger burners aren't hotter, but you get more volume of heat...think Volts and Amps. You'd need to go to Oxy-propane or Oxy-Aetylene to get higher temperatures. It's much harder to screw thing up using propane, you work slower, and it's very hard to over cook the steel.
All the best,
Pause, take a breath and ask yourself: "What would Rastamouse