What are your system specs ? You might not need more than 600w.
Did you try using online PSU calculators? They are a good indicator of what your planned system will consume and the recommended PSU with sufficient overheads.
You are quite limited with your choices since you need SFX PSU.
650W - EVGA Super Nova 650 SFX, Silverstone SX-650G
700W - Silverstone SX-700LPT
750W - Lian-Li PE-750, Corsair SF750
800W - Silverstone SST-SX800-LTI
Note that all these are 80+ Gold rating and up, so they will cost you quite a bit.
At this point it's down to your own leg works to call up the local distros to check if they carry them in. Else it will be Amazon and Newegg.are these psu avail locally? I havent go down SLS personally to check, but did a quick check on the price lists, other than the Silverstone 700LPT (which is a sfx-L, i prefer sfx), cant find the rest u mentioned above.
At this point it's down to your own leg works to call up the local distros to check if they carry them in. Else it will be Amazon and Newegg.
Honestly, I wouldn't mind getting from overseas as PSU can last a while, unless you run it in a dusty place or you're unlucky enough to get a lemon. Heck, my current PSU was from 2012!
