I'd stick with the traynor, not familiar with the peavey head, but Traynors have great tone and your 200 tube watts should easily be able to beat a 500w solid state amp, especially one that requires you to use a 2 ohm load.
My vote is for buying a more efficient speaker set up for the amp you have now. If weight is an issue I'd stick with a cab with neo speakers, but maybe look into buying 2 210 cabinets, or a 410, or larger!
Avatar is a good place to start, very good prices for the quality and they have a nice neo line.
