Sirius heatsinks are available finnaly, and they are cheap;
Mechanical components x 5
Mechanical scrap x 8
Vandium x 6
Niobium x6
I was expecting bit more of "price" per one sink, but wont be complain about it either. I was able to get enough of these sinks to replace all old sinks used in my ships, by one stop at tech broker that sells it.
Just the modified heatsink launcher with extra ammo from the old CG, nothing new here.
Its not just extra ammo, its also lightweight. Only downside is longer reload, but its barely noticable. Single heat sink like that, provided with synth reloads, can keep cold long as one can synth it for extended period of time. This means you can spam heat sink, and when left at 1/1, just basic reload it and by time when you fire last sink, it will reload to full ammo.
Those mats for heat sink reloads are very cheap (G1,G2), and its very easy to get huge amounts at mat traders, and maxed stock of these mats should give like 115+ reloads out of it.