You do not need a 55 gallon kettle to boil 35 gallons. A 35 gallon pot would do the trick, if you can find one. You need some head space to avoid boil-overs, but an extra 20 gallons is a bit much. We use 300,000 or 400,000 BTU banjo burners on our 60 gallon drum kit. Yes it takes a while to get to boil for that much, but we can get about 35 gallons to a boil in under 45 minutes, especially from sparge temp.
I don't think the burners you link to are the most appropriate for your scenario. I would go with something like the Bayou Classic 10" Banjo Burners . The BTU rating is determined by your regulator...hook up to an LP tank with a high pressure regulator and you're good to go with about 350,000 BTUs or so.
Use the regular home brewer March pump, it works fine for large batches and is reasonable in cost -- or maybe buy a chugger if its cheaper? Either or on the pump, as long as it's rated for hot stuff.
And only use Blichmann if you want to spend more than necessary on any equipment. Their products ARE cool, but as a home brewer, don't you WANT to make your own gadgets? Just because they're made by a company in china with better engineering, doesn't really make them better products...mostly they're just more expensive, and less fun (because you don't get to build test and perfect them yourself!)