I have one that fits the bill!
black block stem by KF in nice condition
shiny black alloy with nice bolts (ie no rusty heads!)
twin bolt steerer, four bolt bar clamp
it's 45 or 50mm
can be flipped back normal way (has about 10 degrees +/- rise):EDIT - not really looking for swaps so how about a straight tenner posted?
PARTS FOR SALE:
vintage Brooks Professional saddle | Specialized FACT CX fork | Columbus fork | Reynolds 531 fork | Avid Arch Rival v-brakes | various 700c, 27" and 26" wheels | vintage Weco hubs (fixed/freewheel) | vintage Raleigh ladies frames + lots more!