It is a 27.2 mm alloy seatpost and a steel frame - True Temper AVR. It's an older frame but NOS - I don't think a seatpost has ever been installed.
First few inches were tough but ok. But, I'm still a couple inches from the min insertion line and it's become almost impossible to continue moving the seatpost into the seattube.
How much effort should I put into making this work, or is it more likely that this is a 27.0 seatpost?