Hey Pharaoh, building a "sniper" AK is alot more difficult than slapping a longer inner barrel in there and calling it a day.
If you'd like I've got ALOT of experience with AK's, and I've built long range marksman rifles before. I know you were talking to me about upgrades before -- If you want I could get you an estimate to make you a long range, hard hitting AK
Minimum
Bore-up kit (Piston, Piston head, Cylinder, Nozzle, Cylinder head) - 75
Inner Barrel - 50
Mid-grade hop-up rubber - 8
Hop-up Unit - 20
Long Silencer - 50 to 100
Spring - 15
Total: 218 - 268 + shipping and labor
Recommended:
Bore-up kit (Piston, Piston head, Cylinder, Nozzle, Cylinder head) - 75
Inner Barrel - 50
Top end hop-rubber - 25
Hop-up Unit - 20
Steel outer barrel and bipod - 75 to 150
Spring - 15
Spring Guide - 15
Bushings - 15
Sorbo Pad - 15
Total: 305 - 380 + shipping and labor
Top end:
Bore-up kit (Piston, Piston head, Cylinder, Nozzle, Cylinder head) - 75
Inner Barrel - 115
Top end hop-rubber - 25
Hop-up Unit - 20
Steel outer barrel and bipod - 75 to 150
Spring - 15
Spring Guide - 15
Gears + Bushings - 99
Tappet plate - 9
Sorbo Pad - 15
Total: 448 - 523 + shipping and labor
If you're interested, send me a PM and we can arrange something