Hi there.
Yes price please. I have 2 NOS 8580 R5 the latest model from 90s. And i am looking for at least 1 6581 (1284 su it's me best) to match the other 6581 in my Sammich.
Trade could work, but if the price is nice, I rather buy all the 4 or trade the 2 8580 and buy the other 2.
The 8580s are like new, used couple of hours then swaped with 6581s in my TherapSID.
Let us know. Thank you.