Yeah, that's the issue with cross-site trades, and the only concrete conversion factor is the one currency that is constant across them (how much $1 is worth), so if that's thrown out the window, then anything outside of that system is purely subjective and based on personal valuation, which makes it difficult to negotiate objectively.
That being said, I'm perfectly fine with trading for just the KS, GT, kuhna, and lucain. I believe that comes out to 3.5 mill treasure, as discussed earlier? I would also offer 2mill for the custom kuhna token alone (so the equivalent of 23.5GT), but I think the value you designate it is higher than that, and that's the highest I would go for it.