Alternatively you may be able to use these instead :
Look under UNC Socket Cap Screws.
2-56 3/8 9.53 3/8 9.53 5 MF-SC223 £0.85
25 MF-SC223/25 £3.50
You'll need the required tool to mount it though, he sells good and cheap sets too but do check if the correct size is in the set...