I can get hammertone brown at Bunnings - was thinking IF I cannot get an original, undercoat hammertone brown, then a light green overspray (Mitsubishi - appropriate - metallic lime green) - then a very gentle rub back with 0000 steel wool to remove the lighter from the high "lumps" leaving the lighter green in the "valleys".
Yes, I am anal about colours on scopes - an OCD thing