[Aerkuld]

Isn't it easier to size the pin to the hole, than size the hole to the pin?
That way you can ream the hole to a standard size then turn the pin to whatever size you want to fit the hole. It's usually more difficult to get a hole to the right size when you already have the pin, so it would probably be a good idea to make the hole first in future.

However, if you already have the pin then here's my suggestion. For an interference fit I would think you'd be looking at 1 to 2 thou and a transition fit would be roughly half a thou either side of nominal. But if you want a press fit I would think that anything between 0.0005" to 0.0015" would be fine. You'd probably want to aim for the middle of that range and make it 0.001", but 12L14 is a lead bearing, free cutting, and relatively ductile steel so you shouldn't have any problem if you make it a little on the tight side.

8 thou is WAY too much!