whever I need to do any sort of Rx testing, etc outside of my vehicle, i have been able to power it with a 2s pack, and run my standard 6v servos. I have done it with the crappy duratrax and futaba s3003 servos, as well as my airtronics 94357, and they both run just fine on 2s. and thats with an sr3000 rx.I guess its up to you to see if it will fry your servo or not, but the ones i tested work. In other news, a quick google search found me these:
http://www.readyheli.com/Hitec_HS_79...V_p/37940s.htm
http://www.espritmodel.com/index.asp...OD&ProdID=8942
http://www.pilzers.net/index.php?mai...&products_id=3
http://www.jrradios.com/Products/Tec...dID=JRPS8711HV