The smaller Fullsac baffels are known for making good power and are pretty quiet (I don't know how quiet your pipes need to be over there, would recommend you calling Fullsac and ask them.
Is it an option for you to change the head pipes to an aftermarket pipe that uses the stock heat shields?
I really like the characteristics of the 259 cams, there are some times that I prefer the bike to be a little "softer" on the bottom ( low speed, tight, off camber, uphill switchbacks 2-up & loaded) as it is easier to control for me.
Also like the way the 259s come on and pull to the limiter.
There are other really good cams out there, you just have to be honest with yourself and decide what you want (how you really ride the bike)
'Highly recommend the S&S lifters!! One HD lifter (front intake) just grenaded on the '09 SERG and took out the whole motor

No more HD (jims) lifters for me.
'Just spoke w/ Jamie at FuelMoto this week and asked about larger Throttle Body / Injectors (which he sells) on the new motor, 110 / 259s / 10.5-1 and he promptly told me to save my $$$. I just sent FM the TB to be polished.
I decided to go with the Power Commander V / AutoTune (currently have the SEPST) on the rebuild;
2 good riding friends of mine with 300,000+ miles on their (5) bikes (with built motors) since '06 won't run anything else.
When travelling, I might go from the low desert to 8,000ft in one day. (I like closed loop which a lot of tuners don't do)
Available Octane fuel varies in the US.
I am out of the dyno business!!! If I decide to change any components (heads, cams (with adjustable push rods, it's really easy to try different cams) , intake, exhaust, etc...) at any time, all I have to do is ride the bike.
There are some really good builders with many years of experience on this site, I'm sure they will help you get headed in the right direction.