Hang onto your 8x10 unless you're sick of it being a back breaker. If you do want to get rid of the 8x10, a 215B or 215S which are very similar cabs kick ass. As for your head, Concert Bass, Beta Bass, Coliseum Bass, 880 or 300 all kick ass. And you could even go as far as using a 300T if you can find one *cheap* or Sunn guitar amps, like the Concert Lead (with it's boost and distortion and eerie reverb sounds awesome with bass). If you chose to keep your 8x10 and depending on your luck, where you are and how you go about picking your new head you could get it from $100-$500 as for the cabs that's a grey area, but depending on condition $100-$500 as well. All ball park estimates, the cheapest I've ever paid for any Sunn gear was $45 for a 12 channel mixer that retailed for $1000+ back in the day and $550 for a Concert Lead shipped to me. Basically I am saying you will be happy with whatever you pick provided you get the sound you want but hey they're Sunns, you should get the sound you want no matter.
