It is far easier to buy a FN-6 from China or seize a Soviet/Russian variant from a failing state's coffers, yielding a better chance to take down an airplane than a DIY model. I've been following events in Syria since protests started to get shot up, to the security void created under aerial attacks allowing foreign fighters to swarm in.

For the aspiring MANPAD or Anti-Air battalion a better ROI would probably be what I mentioned above. Evidenced by this is a group having four MANPAD variants in hand enabling me to make a lovely group panorama of the set[1]. For some analysis on the weapons shown in the image you can read a write-up by N.R. Jenzen-Jones including the group shot here[2] or here[3].

This is a lovely exercise for the mind but obviously like most weaponized missile/rocket systems it is best to leave it for the pros. :)

[1] http://imgur.com/gallery/KFH6b04

[2] http://rogueadventurer.com/2013/05/31/9k338-igla-s-and-other...

[3] http://www.armsresearch.org/post/51809092891/9k338-igla-s-sa...