I have my BinalTech Smokescreen using a evangelion sword but i don't know if I have a pic, because it's at work. Also the katana from the Mcfarlane matrix Morpheus figure works good too.
Megazord's Power Sword = Great Sword for Nemesis Prime Or you can buy one of them dirt cheap Transformer Knock-Offs that happen to come with a set of weapons, normally in the form of a longsword and rifle. Keep the weapons, throw away the bot.
Not sure if Predacon swords fit Alternator hands, but they are sized right. For the longest time I had Alt. Sunstreaker holding onto one of those lightsaber missiles from a Star Wars TF. A little smallish, but fit quite well otherwise.
I am scratchbuilding a smaller version of the GFCBrave Max sword for STPrime over at TFans. (Pain in the ass to scale it down) But when its finished I will put pics in the kitbash forum.
I found some "Binal-Tech Arming Kits" on e-Bay. They contain "light sabers" a missile launcher and a sword. The swords come in silver and gold versions. They may be still avaialable.
The GI Joe Sigma 6 line has some badass weapons for the Alts. The hilts are just the right size most of the time brb for a pic edit Have mostly gunpics, but most of the handles are the same
My TRU has these GI Joe Sigma Six motorcycles on clearance for $9. They come with all sorts of swords and knives and stuff. Check your TRU - maybe you'll find the same.
I've got Alt Ricochet holding a Sword from an Exevos set I bought on Clearence, its not perfect, but it holds pretty well.