So I don't know how it happened, maybe it was loose and just fell out, or maybe a Harley guy stole it but I was riding down the road after filling up with petrol and I started to smell petrol

pulled up and saw fuel poring out of the right side carb bowl!

so needless to say I hit the kill switch and turned the fuel tap off asap.
On inspection the carb bowl drain screw was completely missing!!!

I fixed it with some RTV pretty easily but now want to know can these be purchased individually or shall I just leave the RTV there????