This probably should have been posted to the Wacky thread.

That is pretty beat up.

Any idea what the seatpost size is?

If you could get the old post out... then put in a quill/expander/wedge seat post. However, the expanders are relatively rare and expensive, and the frame is hardly worth it. I'm seeing a few that are 27.2mm. Is that the only size?

Maybe $20 for the frame including fork and headset (you could always resell the fork and salvage the dropouts if it doesn't work out).

Could you simply drill it out? I think I have a 1" drill, or one could go incrementally up from 3/4 or 7/8, simply drilling might knock it loose.