Sunn Sorado 6550s

[robbass]

I scored a 1970 Sunn Sorado a couple weeks ago that is in great shape and sounds amazing.  It has two unmatched 6550s; one GE and one RCA.  I would like to get a matching 6550, if possible, but don't know which of the two 6550s is better or if one was possibly an original tube vs. the other.  Any suggestions or ideas?  Thanks!

[N2000s]

If they are both the "coke-bottle" shaped 6550's it's posiable they might be both Tung-sols just rebranded as GE or RCA. From what I understand Tung-Sol was the only one producing the coke bottle 65550's of the era that Sunn was know to use. Do you have a photo of the tubes?
Do they both look like this?

[robbass]

That's the same exact RCA tube I have, thanks dude!  Sorry I don't have any photos posted... being the purist I am, I will look for another RCA (which will be a bit of a challenge).  The amp is great and a tone monster that I play it through my Sunn 215SH.  Once I find a matching cab for my 1983 Coli 300, like a 412L, I will pair the two up for some serious air movement!