Skeettx said he was looking for lighter 7/8 ounce loads. Fiocchi makes a "trainer" 12 gauge 2-3/4" load that is 7/8 ounce of shot (7-1/2 or 8) at 1200 FPS. According to the distributor in the US they are between 6500 and 7500 psi. I called them twice before they would tell me the pressure range. These are not as cheap as Herters or Estates. I have used them a lot in a 12 ga damascus gun with 2-5/8" chambers and long forcing cones, and other 12 gauges.

Another possibility for 2-1/2" fans is at William Larkin Moore. They have custom loads made and sell them in 7/8 ounce 16 and 20 gauge. I have used them in #7 and #7-1/2". WM Larkin Moore's shop is in Scottsdale, AZ. I think they are about $10 a box.