I would look into the Kalibr mini carbine also[img width= height= alt=Image result for kalibr mini carbine]http://www.krale-schietsport.nl/media/catalog/product/cache/1/image/9df78eab33525d08d6e5fb8d27136e95/k/a/kalibrgun-cricket-minicarabine.jpg[/img]
Don't rule out the Brocock Compatto or Bantam They are the perfect balance between bullpup and rifle:No trigger or cocking lever linkages neededNo need to lower the gun or to reach back by your ear to cock itUltra-smooth actionNo need for an ultra-high scope mount/extreme cant sensitivity as on full bullpupsThe .25 Compatto/Bantam are not a full power (50 FPE) one, but somewhere between 30 and 40 FPE, I think. It's also a bit longer, but that's needed to get .25s up to speed without wasting a lot of air.