Hi.
I'll try to shed some light on from my point of view, from when I used to sit in it better.
Swiatek cams:
114 it's cam just for road use. Can't get more then 32-35 bhp from that one with some heavy mods.
385 it's MOST popular road and race. Easy to live with on road and quite tuneable for racing. With at least 2mm head skimm, your carb, -25% of flywheel, mods to timming chain sprocket and ignition and exhaust/inlet you'll see 35 usable bhp easy. I would say even more than that.
760 most extreme from Swiatek's range back then (ca 10 years ago) for 'normal' customers/ of shelf. Require heavy mods to engine: skimm about 6-7mm, recesed pistons, big valves, lightened and balanced components, twin carbs, racing exhausts, light flywheel. Can't use on road, as previously mentioned barely any tickover.
Kaluza 555 !!would get in heart beat. Not so extreme as 760 and better then 385. Can get around 55bhp with right mods. And still can live with it on roads. Hard to get nowadays, there used to be some copys on moto.allegro.pl
There is loads of variations of above and some other small manufacturers that can make custom one for your needs.
In my opinion you should get swiatek 385 (or current equivalent) for your needs. It's absolutely perfect for day to day/weekend use. That cam was introduced when 126 was still in production just wondering why they haven't use it in later models
The above are only my thoughts from 10 years back when I had pleasure to own 126 with Kaluza 555 and drove couple with swiatek 385s, when Breda exhaust(which I have on mine) was only reserved for rally/autograss cars
Also, that is place to look at--->
http://www.motonews.pl/forum/?op=fvf&c=0&f=25 Loads of rally mad members but also some classic lovers
Cheers
