If it was a 10" I think there is a vintage black shadow 10" that mesa briefly sold. I'm thinking E50 by Eminence? If so and you want it you'll have to hit the used market since I don't think it's made anymore. A 10" gold might be worth a try with that amp if it is 10".
Not to be confused with the vintage BS 12" Eminence VS-12 from the 80's.
The 5:50 combo I had sported the MC-90 BS, not to be confused with the 3-6 other versions.......