well p5a + 104 would be good, a103 is abit less eco then the a104. If you dont have the skill yet you could do a p4a as a gun its more eco but does about dps less ( look at entropedia weapon compare

) .
Basicly what to choose for armor and fap. depending on how you wanna play, i'm laizy so i go with ghost + 5b pretty much get no dmg but it isnt the most eco way. shogun worked for my fine in my younger years.
for the fap, well try not to die in fight, if you can manage that you can use vivo T1 or vivo t5. for eco . and maybe a panic fapper if you pull to much at once or crit ( whatever your skilllevel and pedcard makes best for it ).