Serotta Seatpost Sizing

[coolplanetbikes]

Hi All,
I've got a Serotta here with an odd size seat tube. It would appear to take a 31.6 but it won't fit in there - seems to want a 30mm post or so. The collar clamp has an internal diameter of 34.9mm. I'm trying to figure out if a prior owner bent the tube trying to clamp down on a too small post or if there was some other in between size I should be looking for.

Other than 27.2mm, does anyone know what other size seatposts Serottas sometimes take? Was the 34.9mm collar clamp made for frames with 31.6mm posts?

Thanks in advance.