SPD longer bolt needed (recessed shoe)

So the bolt hole on my dbh shoes is recessed for SPD cleats, thus i need a longer bolt that than the 12mm one supplied with the wellgo cleats. I'd say around 15mm will be fine, can anyone recommend where to get one from, tried LBS to no avail.

clerkenwell screws?

Not located in london but thanks.

Might try a hardware shop, kinda hope there was something one, hard to get to the shops with work.

shirley there's screw vendors online? or on ebay?

Any hardware shop, I think they're M5 or M6. Take one to the shop to show them and ask for some 15mm ones in stainless steel. Buy a few extra for spares.

Tried another LBS, a car spares shop and a hardware shop today. All to no avail. Most had nothing with counter-sunk tops. Will try somewhere further afield tomorrow.

On a related point, why does your shoe/cleat combo need longer bolts? Is the cleat thicker than Shimano SPD cleats, or is the sole thicker than usual? I've used SPDs for many years and have never had this problem with any brand of shoe. I [naively] assume that shoe and pedal manufacturers license the design from Shimano and thus have a standard specification.

The bolt hole on the shoe is recessed.

Strange, looking at my shoes the holes are also recessed but the standard bolts seem fine. These are Shimano brand cleat though.

http://www.ebay.co.uk/itm/SPD-cleat-bolts-Shimano-Time-Look-XC-DH-cheapest-16mm-/160620314340?pt=UK_sportsleisure_cycling_bikeparts_SR&hash=item2565b77ee4

Hero^

Beer token owed.