This is exactly what you need. Only problem is they are very expensive;
http://www.scumbackspeakers.com/h_series.html
Yes they are...I do have an empty mid 70's Marshall 4x12 to put some of those into though...:firedevil
Well, if you decide to run 4xG12H30 in that marshall cabinet, youre looking at 120 watts power capability. Thatmeans that it would be just about perfect for a 60 watt amp.
You oughta consider a mix of G12H30/Vintage 30's. Still 120 watts, but a really full tone, but with lots of G12h vibe..