for something a little larger i have used a "dowel pin removal tool"... it is designed to rotate into position over the pin, engage it in a rotary fashion and grip while you turn and lift it. they work really well on pieces 3/16" and larger. i've never used them on something that small, but i know they exist and have heard of them being used.
for something that close to flush, you may have to buy the tool and take it to the grinder to "flatten" its bottom so you can maximize how much you have to clamp on.
this might be your best bet.
machine shops may have them, or some tool stores carry a stud removal tool you can grind or modify for cheap...
i also thought of hooking a car battery and a pair of jumper cables up to this... i wouldn't recommend it, but i have hooked a clamp on a metal piece, then used the other clamp latched on a fender washer... touch the fender washer to the head of the roll pin and it'll weld to it near instantly. of course you have to be ready to grip the clamp off the washer... the chances of this working on something this small is about 20% or less. besides, it might seize or weld the pin in the lower... like i said, it works well on pieces slightly larger in a more loose hole... you can then grab a hold of the washer and work it out of the hole... again, i felt like mentioning it, but don't think it your best option...
septic tank