An 8.5 inch barrel from fab would make an awsome SL8/G36K or C version.
Where would I get that stock however? Like is there a specific airsoft model thats easy to convert?
If your looking for ideas with airsoft stocks, check out the guys at
http: //customrifles.info/forum/YaBB.pl?board=customdisc
They have done some really cool g36 clones from 597's and 10/22s
as well as some step by-steps
If i may also throw the tapco fusion stock in there.. not as tacticool, but so far very sturdy and well made.