Hi
Glad you found the correct or visual match for the floor bolts, yes it is hard to find them now that are not philipshead. I was going to suggest Fastenal
http://www.fastenal.com/web/location...on=selectStore But the nearest international one of their distribution points to you is Singapore, I've had pretty good luck get stuff though some times it takes awhile. The other thing is they only sell in bulk usually 100 in the smaller sizes like the 1/4-20
1/4"-20 x 1" Zinc Plated Slotted Flat Head Machine Screw local cost $13.91 for 100 better that $0.30 each the local hardware store.
The other one that I just ordered and got was 1/4"-20 x 1/2" Slotted Oval Head Zinc Machine Screw which are used on the doors.
Only problem is that the are Zinc plated, to make the paint stick I dip the heads in metal prep used before painting bare steel, then wash. It takes the shine off and helps the paint really stick. I only dip the heads now dumped a bunch in one time let them sit for 1/2 hour and then washed the off, heads painted great but the threads rusted. So now I just put a small amount of the metal prep in a shallow pan and stand the heads in it or just soak a section of cloth and and stand the heads on that.
By the way your doors came out looking great, I had to redo mine because I ended up with sanding scratches showing through the paint.
Cheers Phil