The Eagle ST will not come back. Goodyear will not make enough money making that tire. They make more money on a line that is making replacements for todays vehicles. (Have you seen the price of tires for your daily driver?) Honestly, I am surprised that BFG (parent company Michelin) is still selling the Radial T/A as cheap as they have.
As for the idea of the Polyglas tire being made into a radial tire, I do not see it happening. But, never say never. The reason is that Polyglas is a registered trademark of Goodyear. Goodyear would have to approve and test the design. If you have priced the reproduction radials, then you would get an idea of what these 'boutique' tires would cost. If you think that the Polyglas are expensive, you would not like the cost of the faux tires.
As for Eagles, the Eagle GT is being reproduced in two sizes. 255/60/15 and 215/65/15.
If you have any questions, please feel free to contact me. My cell is 816-654-3400.
Rusty