It weighs .56t per kerbal. Anyway, i decided to use stock lander can and go for class 3 challenge. I want to use parts from RLA Stockalike, Kerbonov (both in "Permitted part mods" list) and TurboNisuReloaded (not in list, but all parts are stockalike) in my mission. Two landers are ready and tested, but mothership is still WIP.