The bolt for the pin is same as a valve cover bolt - 6mm I think.
Pulling this pin can be a real bear, as they tend to sieze a bit.
I never had any luck fabricating a slide hammer that would yank it out.
I just pulled one yesterday by rigging a lever system with a box wrench-one end over the end of the valve cover bolt screwed into the pin, and the other end attached to the bolt holding the idler pulley on on the passenger side of the motor - then get a big bar and pry carefully outward near the pin. Watch the chain guide, very brittle.

Finding a good used 103 engine is not so easy; I looked around awhile recently, and the asking price is $800 and up (plus shipping) for motors with 200k miles. I'm sure there are deals around, but I didn't spot any.

DG