The scale arrived!
The prototype weighs 0.886kg (complete build, with caps and all, of course). In comparison, my Pok3r weighs a little bit less with 0.740kg. Keep in mind, that the prototype has a alu plate inside, while the final design will have a steel plate and will also have a tiny bit more material overall because it is a high profile case. So I estimate a complete build of the final SKB60 to be roughly 1kg. The SKB75 will weigh surely over 1kg.
This, means that I will be able to keep the shipping packages under 2kg. Usually up to 2kg isn't too expensive when shipping internationally.
Not decided jet if I should set a fixed shipping price for all (non-european) orders or if I'll set it per country. Also looking into the possibility of a proxy, but I guess you wouldn't save that much and I would have much more work and organization to do.
And, still got to wait until I'll get the samples, takes a while.