I bought a spare Skystriker expressly for this purpose (and because Amazon had them on sale for 13 bucks). Even at full price though, it's still cheaper than the official version and if you don't care about getting the Cobra Commander or mini-Megs this is a great option.
I don't know if this is the same folks at Reprolabels (they're both Canadian anyway), but I've bought numerous sets from Cobra Stickers and they are very high quality.
*I thought this was ok for this forum, but if it needs to move to Bot Talk, or General - thy will be done.
**Edit: Ok, looking more closely I just realized they have only made an "add-on" set for the Starscream Skystriker, not an actual replica set. They do have one for Thundercracker, but that's it for now. Sorry for the false alarm.
Edited by Dake, 04 March 2012 - 04:34 PM.