Been looking around the stores, but came back empty handed...
Found tappers for M4, the drill hole should be 3.3 mm, but they didn't have the handle for tappers so - nothing for now. Trying to find good quality allen bolts but found nothing - I really mean nothing, no 'allen' bolts of any kind, and the rest of the stuff I found (ordinary bolts) was of suspicious quality.
Gonna look harder tomorrow. Been asking around for barbs, got some info, gotta check it (also tomorrow).
Btw, I tried to remember the ISO number on the tappers and little chart with drill size for M taps, but all I remember is for M4 drill size is 3.3 mm and for M6 is 5 mm. She didn't remember it either. Maybe cos' I didn't ask her to.
I hate waiting....
Thx guys!